:root {
  color-scheme: light;

  --color-canvas: #f7f3ec;
  --color-surface: #fffdfa;
  --color-surface-raised: #ffffff;
  --color-surface-subtle: #faf6f0;
  --color-surface-sunken: var(--color-canvas);
  --color-text: #211b17;
  --color-text-soft: #4f453e;
  --color-text-muted: #756b63;
  --color-border: #e2d9ce;
  --color-primary: #b43b2d;
  --color-primary-hover: #963024;
  --color-primary-soft: #f9e9e5;
  --color-primary-contrast: #ffffff;
  --color-success: #286b48;
  --color-success-soft: #e5f1e9;
  --color-info: #255f98;
  --color-info-soft: #e5eef8;
  --color-accent: #76539b;
  --color-accent-soft: #eee8f6;
  --color-warning: #815a14;
  --color-warning-soft: #f9efd5;
  --color-danger: #a9342b;
  --color-danger-soft: #fae8e5;
  --color-focus: #2868a5;

  /* Legacy aliases stay stable while page modules migrate to semantic tokens. */
  --bg: var(--color-canvas);
  --sur: var(--color-surface);
  --ink: var(--color-text);
  --ink2: var(--color-text-soft);
  --mu: var(--color-text-muted);
  --bd: var(--color-border);
  --rd: var(--color-primary);
  --rds: var(--color-primary-soft);
  --gn: var(--color-success);
  --gns: var(--color-success-soft);
  --bl: var(--color-info);
  --bls: var(--color-info-soft);
  --pu: var(--color-accent);
  --pus: var(--color-accent-soft);
  --am: var(--color-warning);
  --ams: var(--color-warning-soft);
  --primary: var(--color-primary);
  --primary-light: #d95a49;

  --space-1: 4px;
  --space-2: 8px;
  --space-3: 12px;
  --space-4: 16px;
  --space-5: 20px;
  --space-6: 24px;
  --space-7: 28px;
  --space-8: 32px;
  --space-9: 36px;
  --space-10: 40px;
  --space-12: 48px;
  --radius-small: 8px;
  --radius-button: 12px;
  --radius-card: 18px;
  --radius-large: 24px;
  --radius-pill: 999px;
  --radius-sm: var(--radius-small);
  --radius-md: var(--radius-button);
  --radius-lg: var(--radius-card);
  --radius-xl: var(--radius-large);
  --shadow-card: 0 8px 28px rgba(54, 38, 28, 0.07);
  --shadow-raised: 0 16px 40px rgba(54, 38, 28, 0.12);
  --shadow-dropdown: 0 16px 38px rgba(54, 38, 28, 0.14);
  --elevation-1: var(--shadow-card);
  --elevation-2: var(--shadow-raised);
  --focus-ring: 0 0 0 3px rgba(40, 104, 165, 0.28);
  --touch-target: 44px;
  --header-height: 56px;
  --mobile-nav-height: 60px;
  --content-max: 1240px;
  --reading-max: 760px;
  --learning-center-max: 1040px;
  --duration-fast: 140ms;
  --duration-standard: 220ms;
  --duration-slow: 360ms;
  --ease-standard: cubic-bezier(0.2, 0, 0, 1);
  --font-serif: 'Lora', serif;
  --font-sans: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Helvetica, Arial, sans-serif;
}
* { margin:0; padding:0; box-sizing:border-box; }
body {
  background: var(--bg);
  color: var(--ink);
  font-family: var(--font-sans);
  font-weight: 400;
  line-height: 1.5;
  min-height: 100vh;
  min-height: 100dvh;
  text-rendering: optimizeLegibility;
  -webkit-tap-highlight-color: transparent;
}
body.dark {
  color-scheme: dark;
  --color-canvas: #171411;
  --color-surface: #211d19;
  --color-surface-raised: #29231e;
  --color-surface-subtle: #211d19;
  --color-surface-sunken: var(--color-canvas);
  --color-text: #f4eee7;
  --color-text-soft: #d0c6bc;
  --color-text-muted: #aaa096;
  --color-border: #3a322c;
  --color-primary: #e06a58;
  --color-primary-hover: #ef806d;
  --color-primary-soft: #43221d;
  --color-primary-contrast: #211b17;
  --color-success: #74b98f;
  --color-success-soft: #183326;
  --color-info: #78aee0;
  --color-info-soft: #172b40;
  --color-accent: #b79adb;
  --color-accent-soft: #2c213b;
  --color-warning: #d7aa55;
  --color-warning-soft: #392d18;
  --color-danger: #ef8175;
  --color-danger-soft: #43211d;
  --color-focus: #83b9eb;
  --shadow-card: 0 10px 30px rgba(0, 0, 0, 0.28);
  --shadow-raised: 0 18px 46px rgba(0, 0, 0, 0.38);
  --shadow-dropdown: 0 18px 42px rgba(0, 0, 0, 0.42);
  --focus-ring: 0 0 0 3px rgba(131, 185, 235, 0.32);
}

button,
input,
select,
textarea {
  font: inherit;
}

button,
[role="button"],
a {
  touch-action: manipulation;
}

:where(button, input, select, textarea, a[href], [tabindex]):focus-visible {
  outline: 2px solid var(--color-focus);
  outline-offset: 2px;
  box-shadow: var(--focus-ring);
}

::selection {
  color: var(--color-text);
  background: var(--color-warning-soft);
}

.wd, .wb-word, .word-rank-word, .colloc-es, .exes {
  font-family: var(--font-serif) !important;
}

/* 可复用组件 */
.card {
  background: var(--sur);
  border: 1px solid var(--bd);
  border-radius: var(--radius-card);
  padding: 16px;
  box-shadow: var(--shadow-card);
  transition: box-shadow 0.2s, transform 0.2s;
}
.card:hover {
  box-shadow: 0 8px 24px rgba(0,0,0,0.1);
  transform: translateY(-2px);
}

.pill {
  display: inline-flex;
  align-items: center;
  padding: 6px 16px;
  border-radius: var(--radius-pill);
  font-size: 0.8rem;
  font-weight: 500;
  background: var(--bg);
  border: 1px solid var(--bd);
  color: var(--ink2);
  cursor: pointer;
  transition: all 0.15s;
  white-space: nowrap;
}
.pill:hover { border-color: var(--rd); color: var(--rd); }
.pill.on { background: var(--rd); border-color: var(--rd); color: #fff; }
.pill.small { padding: 4px 12px; font-size: 0.7rem; }
.pill.large { padding: 8px 20px; font-size: 0.9rem; }

.icon-btn {
  width: 44px;
  height: 44px;
  border-radius: 50%;
  background: transparent;
  border: none;
  color: var(--ink);
  font-size: 1.2rem;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  transition: background 0.15s;
}
.icon-btn:hover { background: rgba(0,0,0,0.05); }
body.dark .icon-btn:hover { background: rgba(255,255,255,0.1); }
.tb-r .icon-btn { color: #fff !important; }
.glass {
  background: rgba(255,255,255,0.8);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  border: 1px solid rgba(255,255,255,0.2);
}
body.dark .glass {
  background: rgba(20,18,16,0.8);
  border-color: rgba(255,255,255,0.1);
}
/* 顶部导航 */
.tb {
  background: var(--ink);
  height: 52px;
  padding: 0 20px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  position: sticky;
  top: 0;
  z-index: 100;
  box-shadow: 0 2px 12px rgba(0,0,0,.3);
}
.logo {
  font-family: 'Lora', serif;
  font-size: 1.05rem;
  font-weight: 700;
  color: #fff;
  display: flex;
  align-items: center;
  gap: 8px;
}
.logo-pip {
  width: 8px;
  height: 8px;
  background: var(--rd);
  border-radius: 50%;
}
.logo sub {
  font-size: .68rem;
  color: rgba(255,255,255,.4);
  font-weight: 300;
  letter-spacing: .04em;
}
.tb-r { display: flex; gap: 8px; align-items: center; }
/* Hero区域 */
.hero {
  background: var(--ink);
  padding: 20px 20px 16px;
  text-align: center;
  overflow: hidden;
  position: relative;
}
.hero::before {
  content: 'ESP';
  font-family: 'Lora', serif;
  font-size: 6rem;
  font-weight: 700;
  color: rgba(255,255,255,.03);
  position: absolute;
  left: 50%;
  top: 50%;
  transform: translate(-50%,-50%);
  pointer-events: none;
  white-space: nowrap;
}
.hero h1 {
  font-family: 'Lora', serif;
  font-size: 1.5rem;
  font-weight: 700;
  color: #fff;
  line-height: 1.2;
  margin-bottom: 12px;
}
.hero h1 em { font-style: italic; color: #e8a080; }

.stats {
  display: flex;
  justify-content: center;
  margin-top: 20px;
  padding-top: 16px;
  border-top: 1px solid rgba(255,255,255,.08);
  flex-wrap: wrap;
}
.stat {
  padding: 0 16px;
  text-align: center;
  border-right: 1px solid rgba(255,255,255,.08);
}
.stat:last-child { border-right: none; }
.sn {
  font-family: 'Lora', serif;
  font-size: 1.2rem;
  font-weight: 700;
  color: #fff;
}
.sl {
  font-size: .58rem;
  color: rgba(255,255,255,.4);
  letter-spacing: .08em;
  text-transform: uppercase;
  margin-top: 2px;
}
@media (max-width: 767px) {
  .stats-desktop { display: none; }
}
/* 控制区（搜索+胶囊） */
.ctrl {
  background: var(--sur);
  border-bottom: 1px solid var(--bd);
  padding: 12px 18px;
  position: sticky;
  top: 52px;
  z-index: 90;
  box-shadow: 0 1px 6px rgba(0,0,0,.06);
}
/* 水平布局容器 */
.filter-row {
  display: flex;
  align-items: center;
  gap: 8px;
  flex-wrap: nowrap;
  width: 100%;
}

/* 主胶囊组：固定宽度不压缩，可横向滚动 */
.filter-capsules {
  display: flex;
  gap: 8px;
  overflow-x: auto;
  flex-shrink: 0;
  scrollbar-width: none;
}
.filter-capsules::-webkit-scrollbar {
  display: none;
}

/* 已选条件区域：占据剩余宽度，可横向滚动 */
.active-filters {
  display: flex;
  gap: 8px;
  overflow-x: auto;
  flex: 1 1 auto;
  min-width: 0;
  scrollbar-width: none;
}
.active-filters::-webkit-scrollbar {
  display: none;
}

/* 无内容时隐藏区域 */
.active-filters:empty {
  display: none;
}

/* 已选条件标签样式（您之前已有，这里仅为确保） */
.active-filter {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 6px 12px;
  background: var(--rds);
  border: 1px solid var(--rd);
  border-radius: 30px;
  font-size: 0.8rem;
  color: var(--rd);
  white-space: nowrap;
}
.active-filter .remove {
  cursor: pointer;
  font-weight: bold;
  margin-left: 4px;
}
.active-filter .filter-tag {
  font-weight: 500;
}
.active-filter .filter-count {
  background: rgba(184,58,42,0.1);
  border-radius: 16px;
  padding: 2px 6px;
  font-size: 0.7rem;
  color: var(--rd);
  margin-left: 2px;
}
/* 搜索框 */
.search-container {
  display: flex;
  align-items: center;
  background: rgba(255,255,255,0.8);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  border-radius: 25px;
  padding: 0 12px;
  margin-bottom: 12px;
  border: 1px solid var(--bd);
  transition: border-color 0.2s;
}
.search-container:focus-within {
  border-color: var(--rd);
}
.search-icon {
  color: var(--mu);
  font-size: 1rem;
  margin-right: 8px;
}
.search-input {
  flex: 1;
  height: 44px;
  border: none;
  background: transparent;
  font-size: 0.9rem;
  color: var(--ink);
  outline: none;
}
.search-input::placeholder { color: var(--mu); }
.search-clear {
  width: 30px;
  height: 30px;
  border: none;
  background: transparent;
  color: var(--mu);
  font-size: 1.2rem;
  cursor: pointer;
  display: none;
  align-items: center;
  justify-content: center;
}
.search-clear.show { display: flex; }
body.dark .search-container {
  background: rgba(20,18,16,0.8);
  border-color: rgba(255,255,255,0.1);
}

/* 胶囊组 */
.filter-capsules {
  display: flex;
  gap: 8px;
  overflow-x: auto;
  padding-bottom: 4px;
  margin-bottom: 8px;
  scrollbar-width: none;
}
.filter-capsules::-webkit-scrollbar { display: none; }
.capsule-wrapper {
  position: relative;
  flex-shrink: 0;
  overflow: visible;
}
.capsule {
  padding: 10px 20px;
  background: var(--bg);
  border: 1px solid var(--bd);
  border-radius: 40px;
  font-size: 0.9rem;
  font-weight: 500;
  color: var(--ink2);
  cursor: pointer;
  white-space: nowrap;
  transition: all 0.2s ease;
  box-shadow: 0 2px 4px rgba(0,0,0,0.02);
}
.capsule:hover {
  background: var(--sur);
  border-color: var(--rd);
  transform: translateY(-1px);
  box-shadow: 0 4px 8px rgba(0,0,0,0.05);
}
.capsule.active {
  background: var(--rd);
  border-color: var(--rd);
  color: #fff;
  box-shadow: 0 4px 12px rgba(184,58,42,0.3);
}
.capsule::after {
  content: '▼';
  font-size: 0.7rem;
  margin-left: 6px;
  opacity: 0.7;
}
.capsule.active::after { color: #fff; }
/* 已选条件胶囊条 - 横向滚动 */
.active-filters {
  display: flex;
  gap: 8px;
  overflow-x: auto;
  flex: 1 1 auto;
  min-width: 0;
  margin-top: 8px;
  padding: 4px 10px;
  font-size: 0.75rem;
  scrollbar-width: none;
}
.active-filters::-webkit-scrollbar {
  display: none;
}
.active-filter {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 6px 12px;
  background: var(--rds);
  border: 1px solid var(--rd);
  border-radius: 30px;
  font-size: 0.8rem;
  color: var(--rd);
  white-space: nowrap;
  cursor: default;
}
.active-filter .remove {
  cursor: pointer;
  font-weight: bold;
  font-size: 1.1rem;
  line-height: 1;
  opacity: 0.7;
  transition: opacity 0.2s;
  margin-left: 4px;
}
.active-filter .remove:hover {
  opacity: 1;
}
/* 主内容区域 */
.main {
  max-width: 760px;
  margin: 0 auto;
  padding: 18px 15px 60px;
}
.wl {
  display: flex;
  flex-direction: column;
  gap: 12px;
}
/* 手机端隐藏统计数字 */
@media (max-width: 767px) {
  .stats-desktop {
    display: none;
  }
}
.tip-bar {
  margin-bottom: 10px;
  font-size: .7rem;
  color: var(--mu);
  background: var(--bls);
  padding: 6px 12px;
  border-radius: 6px;
  display: flex;
  align-items: center;
  gap: 8px;
  border-left: 3px solid var(--bl);
}
.tip-bar span { color: var(--bl); font-weight: 500; }
.sb {
  display: flex;
  align-items: center;
  gap: 9px;
  background: var(--bg);
  border: 1px solid var(--bd);
  border-radius: 6px;
  padding: 8px 13px;
  margin-bottom: 10px;
  transition: border-color .2s;
}
.sb:focus-within { border-color: var(--rd); }
.si {
  flex: 1;
  border: none;
  background: none;
  font: 300 .83rem 'Noto Sans SC', sans-serif;
  color: var(--ink);
  outline: none;
}
.si::placeholder { color: var(--mu); }
.sc {
  border: none;
  background: none;
  color: var(--mu);
  cursor: pointer;
  font-size: .72rem;
  display: none;
}
.sc.show { display: block; }
.frow {
  display: flex;
  gap: 6px;
  overflow-x: auto;
  scrollbar-width: none;
  padding-bottom: 2px;
}
.frow::-webkit-scrollbar { display: none; }
.fdiv {
  width: 1px;
  background: var(--bd);
  margin: 0 3px;
  flex-shrink: 0;
}
.fb {
  padding: 4px 11px;
  border: 1px solid var(--bd);
  background: var(--bg);
  border-radius: var(--radius-pill);
  font: 300 .65rem 'Noto Sans SC', sans-serif;
  color: var(--mu);
  cursor: pointer;
  white-space: nowrap;
  transition: all .15s;
  flex-shrink: 0;
}
.fb:hover { border-color: var(--rd); color: var(--rd); }
.fb.on { background: var(--rd); border-color: var(--rd); color: #fff; font-weight: 500; }

.vrow {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 14px;
}
.rc {
  font-size: .7rem;
  color: var(--mu);
}
.vbtns {
  display: flex;
  gap: 4px;
}
.vb {
  width: 28px;
  height: 28px;
  border: 1px solid var(--bd);
  background: var(--sur);
  border-radius: 4px;
  cursor: pointer;
  font-size: .72rem;
  color: var(--mu);
  display: flex;
  align-items: center;
  justify-content: center;
  transition: all .15s;
}
.vb.on {
  background: var(--ink);
  color: #fff;
  border-color: var(--ink);
}
.wl.gv {
  -webkit-columns: 2;
  -moz-columns: 2;
  columns: 2;
  column-gap: 12px;
}
.wl.gv .wc, .wl.gv .pw {
  break-inside: avoid;
  -webkit-column-break-inside: avoid;
  page-break-inside: avoid;
  margin-bottom: 12px;
  display: inline-block;
  width: 100%;
  vertical-align: top;
}
@media (max-width:600px) { .wl.gv { -webkit-columns: 1; columns: 1; } }
.wc {
  background: var(--sur);
  border: 1px solid var(--bd);
  border-radius: var(--radius-card);
  box-shadow: var(--shadow-card);
  transition: box-shadow .2s, transform .2s;
  position: relative;
  cursor: pointer;
}
.wc:hover {
  box-shadow: 0 4px 18px rgba(0,0,0,.1);
  transform: translateY(-1px);
}
.ct {
  padding: 13px 15px 10px;
  border-bottom: 1px solid var(--bd);
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  gap: 10px;
}
.ct-l { flex: 1; min-width: 0; }
.wd {
  font-family: 'Lora', serif;
  font-size: 1.45rem;
  font-weight: 700;
  line-height: 1;
  margin-bottom: 5px;
}
.wm {
  display: flex;
  align-items: center;
  gap: 6px;
  flex-wrap: wrap;
}
.ph {
  font-family: 'JetBrains Mono', monospace;
  font-size: .7rem;
  color: var(--mu);
}
.pt {
  font-size: .58rem;
  padding: 1px 7px;
  border-radius: 20px;
  background: var(--rds);
  color: var(--rd);
}
.vt {
  font-size: .56rem;
  padding: 1px 6px;
  border-radius: 20px;
}
.reg { background: var(--gns); color: var(--gn); }
.irr { background: var(--pus); color: var(--pu); }

.sb2 {
  width: 30px;
  height: 30px;
  border-radius: 50%;
  border: 1px solid var(--bd);
  background: var(--bg);
  cursor: pointer;
  font-size: .8rem;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: all .15s;
}
.sb2:hover { background: var(--rds); border-color: var(--rd); }
.sb2.playing { background: var(--rd); border-color: var(--rd); color: #fff; }
/* 缩小朗读按钮 */
.speak-btn {
  width: 20px;
  height: 20px;
  font-size: 0.9rem;
  min-width: 20px;
  min-height: 20px;
}
.cb {
  font-size: .62rem;
  padding: 3px 10px;
  border-radius: 20px;
  font-weight: 600;
  letter-spacing: .06em;
}
.A1 { background: var(--gns); color: var(--gn); }
.A2 { background: var(--bls); color: var(--bl); }
.B1 { background: var(--pus); color: var(--pu); }
.B2 { background: var(--rds); color: var(--rd); }
.C1, .C2 { background: var(--ams); color: var(--am); }
.ir {
  padding: 7px 15px;
  border-bottom: 1px solid var(--bd);
  display: flex;
  gap: 9px;
  align-items: flex-start;
}
.ir:last-of-type { border-bottom: none; }
.irl {
  font-size: .56rem;
  color: var(--mu);
  letter-spacing: .1em;
  text-transform: uppercase;
  min-width: 34px;
  padding-top: 3px;
  flex-shrink: 0;
}
.irv {
  font-size: .78rem;
  color: var(--ink);
  line-height: 1.6;
  flex: 1;
}
.col {
  font-family: 'JetBrains Mono', monospace;
  font-size: .7rem;
  color: var(--bl);
}
.conf {
  color: var(--am);
  font-size: .72rem;
}
.mem {
  color: var(--gn);
  font-size: .72rem;
  font-style: italic;
}
.translation { color: #888; margin-left: 8px; }
.chips {
  display: flex;
  gap: 5px;
  flex-wrap: wrap;
}
.chip {
  font-size: .56rem;
  padding: 2px 7px;
  background: var(--bg);
  border: 1px solid var(--bd);
  border-radius: 3px;
  color: var(--mu);
}
.cefr-chip {
  border: none !important;
  padding: 3px 9px !important;
  font-size: .6rem !important;
  font-weight: 600 !important;
  border-radius: 20px !important;
}
.cs { border-top: 2px solid var(--bd); }
.ch {
  padding: 8px 15px;
  background: var(--bg);
  border-bottom: 1px solid var(--bd);
  display: flex;
  align-items: center;
  gap: 7px;
}
.cht {
  font-size: .66rem;
  font-weight: 500;
  color: var(--ink2);
  letter-spacing: .04em;
  display: flex;
  align-items: center;
  gap: 7px;
}
.cht::before {
  content: '';
  display: block;
  width: 3px;
  height: 12px;
  background: var(--rd);
  border-radius: 2px;
  flex-shrink: 0;
}
.mood { border-bottom: 1px solid var(--bd); }
.mood:last-child { border-bottom: none; }
.mt {
  width: 100%;
  padding: 8px 15px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  background: none;
  border: none;
  cursor: pointer;
  text-align: left;
  transition: background .15s;
}
.mt:hover { background: rgba(0,0,0,.02); }
.ml {
  display: flex;
  align-items: center;
  gap: 7px;
}
.mp {
  width: 7px;
  height: 7px;
  border-radius: 50%;
  flex-shrink: 0;
}
.pi { background: var(--bl); }
.pc { background: var(--am); }
.ps { background: var(--pu); }
.da-origin { background: #3498db; }
.da-usage { background: #e67e22; }
.da-mistake { background: #e74c3c; }
.da-exam { background: #9b59b6; }
.da-syn { background: #27ae60; }
.da-family { background: #95a5a6; }
.mn {
  font-size: .72rem;
  font-weight: 500;
  color: var(--ink);
}
.mh {
  font-size: .6rem;
  color: var(--mu);
}
.mk {
  font-size: .58rem;
  color: var(--mu);
  background: var(--bd);
  padding: 1px 6px;
  border-radius: 20px;
}
.ma {
  font-size: .58rem;
  color: var(--mu);
  transition: transform .25s;
}
.ma.open { transform: rotate(180deg); color: var(--rd); }
.mb {
  display: none;
  padding: 14px 16px;
  background: var(--bg);
}
.mb.open { display: block; }
.tps {
  display: flex;
  gap: 5px;
  flex-wrap: wrap;
  margin-bottom: 9px;
}
.tp {
  padding: 3px 9px;
  border: 1px solid var(--bd);
  background: var(--sur);
  border-radius: 20px;
  font: 300 .62rem 'Noto Sans SC', sans-serif;
  color: var(--mu);
  cursor: pointer;
  transition: all .15s;
  white-space: nowrap;
}
.tp:hover { border-color: var(--rd); color: var(--rd); }
.tp.on { background: var(--rd); border-color: var(--rd); color: #fff; }
.tpn { display: none; }
.tpn.on { display: block; }
.tl {
  font-size: .56rem;
  letter-spacing: .1em;
  text-transform: uppercase;
  color: var(--mu);
  margin-bottom: 7px;
  display: flex;
  align-items: center;
  gap: 5px;
}
.tl::after {
  content: '';
  flex: 1;
  height: 1px;
  background: var(--bd);
}
.cg {
  display: grid;
  grid-template-columns: 1fr 1fr;
  column-gap: 10px;
}
.cr {
  display: flex;
  gap: 5px;
  padding: 4px 0;
  border-bottom: 1px solid var(--bd);
  align-items: baseline;
}
.cr:nth-child(3), .cr:nth-child(6) { border-bottom: none; }
.pr {
  font-family: 'JetBrains Mono', monospace;
  font-size: .62rem;
  color: var(--mu);
  min-width: 58px;
  flex-shrink: 0;
}
.cf {
  font-family: 'Lora', serif;
  font-size: .82rem;
  color: var(--ink);
}
.cf .ax { color: var(--gn); }
.anote {
  margin-top: 6px;
  font-size: .62rem;
  color: var(--gn);
  background: var(--gns);
  padding: 4px 8px;
  border-radius: 3px;
}
.ex {
  padding: 10px 15px 13px;
  border-top: 1px solid var(--bd);
  background: var(--bg);
}
.exl {
  font-size: .56rem;
  letter-spacing: .1em;
  text-transform: uppercase;
  color: var(--mu);
  margin-bottom: 8px;
}
.exi { margin-bottom: 8px; cursor: pointer; }
.exi:last-child { margin-bottom: 0; }
.exes {
  font-family: 'Lora', serif;
  font-style: italic;
  font-size: .8rem;
  color: var(--ink);
  line-height: 1.4;
  display: flex;
  gap: 5px;
}
.exes::before {
  content: '"';
  color: var(--rd);
  font-size: .95rem;
  line-height: 1;
  flex-shrink: 0;
}
.exzh {
  font-size: .7rem;
  color: var(--mu);
  padding-left: 13px;
  margin-top: 1px;
}
.pw { position: relative; }
.pwb {
  filter: blur(5px);
  user-select: none;
  opacity: .45;
}
.pwo {
  position: absolute;
  inset: 0;
  background: linear-gradient(to bottom, transparent 0%, rgba(247,244,238,.96) 45%, var(--bg) 100%);
  display: flex;
  align-items: flex-end;
  justify-content: center;
  padding-bottom: 22px;
  border-radius: 6px;
}
body.dark .pwo {
  background: linear-gradient(to bottom, transparent 0%, rgba(20,18,16,.96) 45%, var(--bg) 100%);
}
.pwi { text-align: center; }
.pwi-icon {
  font-size: 1.4rem;
  margin-bottom: 5px;
}
.pwi-word {
  font-family: 'Lora', serif;
  font-size: .9rem;
  font-weight: 700;
  margin-bottom: 3px;
}
.pwi-sub {
  font-size: .7rem;
  color: var(--mu);
  margin-bottom: 10px;
}
.pwi-btn {
  display: inline-block;
  padding: 7px 20px;
  background: var(--rd);
  color: #fff;
  border: none;
  border-radius: var(--radius-button);
  font: 500 .72rem 'Noto Sans SC', sans-serif;
  cursor: pointer;
  letter-spacing: .04em;
  transition: opacity .2s;
}
.pwi-btn:hover { opacity: .85; }
.mo {
  display: none;
  position: fixed;
  inset: 0;
  background: rgba(28,24,20,.75);
  z-index: 2000;
  align-items: center;
  justify-content: center;
  backdrop-filter: blur(4px);
}
.mo.show { display: flex; }
.md {
  background: var(--sur);
  border-radius: 8px;
  padding: 30px 26px;
  width: 90%;
  max-width: 340px;
  box-shadow: 0 12px 50px rgba(0,0,0,.25);
  text-align: center;
  position: relative;
  animation: pop .2s ease;
}
@keyframes pop {
  from { transform: scale(.9); opacity: 0; }
  to { transform: scale(1); opacity: 1; }
}
.mc2 {
  position: absolute;
  top: 12px;
  right: 14px;
  background: none;
  border: none;
  font-size: 1rem;
  cursor: pointer;
  color: var(--mu);
}
.mc2:hover { color: var(--ink); }
.md-icon {
  font-size: 1.8rem;
  margin-bottom: 12px;
}
.md-title {
  font-family: 'Lora', serif;
  font-size: 1rem;
  font-weight: 700;
  margin-bottom: 6px;
}
.md-sub {
  font-size: .73rem;
  color: var(--mu);
  margin-bottom: 18px;
  line-height: 1.65;
}
.pb {
  display: flex;
  border: 1px solid var(--bd);
  border-radius: 4px;
  overflow: hidden;
  margin-bottom: 8px;
  transition: border-color .2s;
}
.pb:focus-within { border-color: var(--rd); }
.pi2 {
  flex: 1;
  padding: 9px 12px;
  border: none;
  outline: none;
  font: 400 .82rem 'JetBrains Mono', monospace;
  color: var(--ink);
  background: var(--bg);
  text-transform: uppercase;
  letter-spacing: .06em;
}
.ps2 {
  padding: 9px 14px;
  background: var(--rd);
  border: none;
  color: #fff;
  cursor: pointer;
  font-size: .82rem;
  transition: opacity .2s;
}
.ps2:hover { opacity: .85; }
.pe {
  font-size: .7rem;
  color: var(--rd);
  display: none;
  margin-bottom: 6px;
}
.pe.show { display: block; }
.md-note {
  font-size: .65rem;
  color: var(--mu);
}
.md-note a { color: var(--rd); text-decoration: none; }

.brand-info-modal {
  width: min(92vw, 620px);
  max-width: 620px;
  max-height: min(88vh, 760px);
  padding: 34px;
  overflow-y: auto;
  text-align: left;
  border: 1px solid var(--bd);
  border-radius: 20px;
}

.brand-info-modal .mc2 {
  width: var(--touch-target);
  height: var(--touch-target);
  top: 12px;
  right: 12px;
  border-radius: 50%;
}

.brand-info-modal .mc2:hover,
.brand-info-modal .mc2:focus-visible {
  background: var(--bg);
}

.brand-modal-kicker {
  margin-bottom: 10px;
  color: var(--rd);
  font-size: .7rem;
  font-weight: 800;
  letter-spacing: .16em;
}

.brand-info-modal .md-title {
  max-width: 500px;
  margin-bottom: 10px;
  padding-right: 36px;
  font-size: clamp(1.35rem, 4vw, 2rem);
  line-height: 1.25;
}

.brand-modal-intro {
  margin: 0 0 22px;
  color: var(--mu);
  font-size: .9rem;
  line-height: 1.8;
}

.feedback-email-card,
.about-contact-card {
  display: flex;
  align-items: center;
  gap: 12px;
  margin-bottom: 22px;
  padding: 14px 16px;
  background: var(--bg);
  border: 1px solid var(--bd);
  border-radius: 12px;
}

.feedback-email-card > span,
.about-contact-card span {
  color: var(--mu);
  font-size: .72rem;
}

.feedback-email-card a,
.about-contact-card a {
  min-width: 0;
  color: var(--ink);
  font-size: .88rem;
  font-weight: 700;
  overflow-wrap: anywhere;
  text-decoration-color: color-mix(in srgb, var(--rd) 42%, transparent);
  text-underline-offset: 3px;
}

.brand-text-button {
  min-height: var(--touch-target);
  margin-left: auto;
  padding: 0 14px;
  color: var(--rd);
  background: var(--sur);
  border: 1px solid var(--bd);
  border-radius: 999px;
  cursor: pointer;
  font-weight: 700;
  white-space: nowrap;
}

.feedback-form {
  display: grid;
  gap: 8px;
}

.feedback-form label {
  color: var(--ink);
  font-size: .76rem;
  font-weight: 700;
}

.feedback-form label span {
  color: var(--mu);
  font-size: .68rem;
  font-weight: 400;
}

.feedback-form input,
.feedback-form select,
.feedback-form textarea {
  width: 100%;
  min-height: var(--touch-target);
  padding: 11px 12px;
  color: var(--ink);
  background: var(--bg);
  border: 1px solid var(--bd);
  border-radius: 10px;
  font: inherit;
}

.feedback-form textarea {
  min-height: 130px;
  resize: vertical;
}

.feedback-form input:focus,
.feedback-form select:focus,
.feedback-form textarea:focus {
  border-color: var(--rd);
  outline: 3px solid color-mix(in srgb, var(--rd) 14%, transparent);
}

.feedback-form-row {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 12px;
  margin-top: 6px;
}

.feedback-form-row > div {
  display: grid;
  gap: 8px;
}

.brand-primary-button {
  min-height: 48px;
  margin-top: 10px;
  color: #fff;
  background: var(--rd);
  border: 0;
  border-radius: 12px;
  cursor: pointer;
  font-size: .9rem;
  font-weight: 800;
}

.brand-primary-button:hover {
  opacity: .9;
}

.brand-modal-note {
  margin: 12px 0 0;
  color: var(--mu);
  font-size: .7rem;
  line-height: 1.7;
}

.about-brand-mark {
  display: grid;
  place-items: center;
  width: 52px;
  height: 52px;
  margin-bottom: 18px;
  color: #fff;
  background: #173f3a;
  border-radius: 14px;
  font-family: 'Lora', serif;
  font-size: 1.7rem;
  font-style: italic;
  font-weight: 700;
  box-shadow: 7px 7px 0 color-mix(in srgb, var(--rd) 18%, transparent);
}

.about-principles {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 10px;
  margin-bottom: 22px;
}

.about-principles article {
  padding: 16px;
  background: var(--bg);
  border: 1px solid var(--bd);
  border-radius: 12px;
}

.about-principles strong,
.about-principles span {
  display: block;
}

.about-principles strong {
  margin-bottom: 7px;
  color: var(--ink);
  font-size: .82rem;
}

.about-principles span {
  color: var(--mu);
  font-size: .72rem;
  line-height: 1.65;
}

.about-contact-card {
  justify-content: space-between;
  margin-bottom: 16px;
}

.about-contact-card > div {
  display: grid;
  gap: 4px;
}

.about-footer {
  color: var(--mu);
  font-size: .68rem;
  letter-spacing: .04em;
}

@media (max-width: 600px) {
  .brand-info-modal {
    width: calc(100vw - 24px);
    max-height: calc(100dvh - 24px);
    padding: 28px 20px 22px;
    border-radius: 16px;
  }

  .feedback-form-row,
  .about-principles {
    grid-template-columns: 1fr;
  }

  .feedback-email-card,
  .about-contact-card {
    align-items: flex-start;
    flex-wrap: wrap;
  }

  .feedback-email-card .brand-text-button,
  .about-contact-card .brand-text-button {
    width: 100%;
    margin-left: 0;
  }
}

.empty {
  text-align: center;
  padding: 60px 20px;
  color: var(--mu);
}
.empty-icon {
  font-size: 2.5rem;
  margin-bottom: 12px;
  opacity: .4;
}
.empty p { font-size: .8rem; }
@media (max-width:480px) {
  .cg { grid-template-columns: 1fr; }
  .stats { gap: 0; }
  .stat { padding: 0 10px; }
}
.colloc-item {
  display: inline-flex;
  flex-direction: column;
  gap: 1px;
}
.colloc-es {
  font-family: 'JetBrains Mono', monospace;
  font-size: .7rem;
  color: var(--bl);
}
.colloc-zh {
  font-size: .6rem;
  color: var(--mu);
}
.colloc-sep {
  color: var(--bd);
  margin: 0 6px;
  font-size: .7rem;
  vertical-align: top;
  padding-top: 2px;
}
.irv.col {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  align-items: flex-start;
}
.page-tabs {
  background: var(--ink);
  display: flex;
  border-top: 1px solid rgba(255,255,255,.08);
}
.ptab {
  flex: 1;
  padding: 11px 0;
  background: none;
  border: none;
  color: rgba(255,255,255,.45);
  font: 300 .72rem 'Noto Sans SC', sans-serif;
  cursor: pointer;
  letter-spacing: .04em;
  border-bottom: 2px solid transparent;
  transition: all .2s;
}
.ptab:hover { color: rgba(255,255,255,.8); }
.ptab.on {
  color: #fff;
  border-bottom-color: var(--rd);
  font-weight: 500;
}
.page-view { display: none; }
.page-view.on { display: block; }
.progress-strip {
  background: rgba(255,255,255,.06);
  border-top: 1px solid rgba(255,255,255,.08);
  padding: 12px 20px;
  display: flex;
  align-items: center;
  gap: 14px;
}
.prog-label {
  font-size: .65rem;
  color: rgba(255,255,255,.5);
  white-space: nowrap;
}
.prog-bar {
  flex: 1;
  height: 5px;
  background: rgba(255,255,255,.1);
  border-radius: 10px;
  overflow: hidden;
}
.prog-fill {
  height: 100%;
  background: linear-gradient(90deg, var(--rd), #e06050);
  border-radius: 10px;
  transition: width .6s ease;
}
.prog-pct {
  font-size: .7rem;
  color: #fff;
  font-weight: 500;
  white-space: nowrap;
  min-width: 32px;
  text-align: right;
}
.quiz-wrap {
  max-width: 600px;
  margin: 0 auto;
  padding: 24px 16px 60px;
}
.quiz-settings {
  background: var(--sur);
  border: 1px solid var(--bd);
  border-radius: 8px;
  padding: 18px 18px;
  margin-bottom: 20px;
}
.qs-title {
  font-size: .75rem;
  font-weight: 500;
  color: var(--ink2);
  margin-bottom: 14px;
  letter-spacing: .04em;
}
.qs-row {
  display: flex;
  gap: 8px;
  flex-wrap: wrap;
  margin-bottom: 12px;
  align-items: center;
}
.qs-label {
  font-size: .62rem;
  color: var(--mu);
  min-width: 44px;
  flex-shrink: 0;
}
.qbtn {
  padding: 4px 12px;
  border: 1px solid var(--bd);
  background: var(--bg);
  border-radius: 20px;
  font: 300 .65rem 'Noto Sans SC', sans-serif;
  color: var(--mu);
  cursor: pointer;
  transition: all .15s;
  white-space: nowrap;
}
.qbtn:hover { border-color: var(--rd); color: var(--rd); }
.qbtn.on { background: var(--rd); border-color: var(--rd); color: #fff; }
.start-quiz-btn {
  width: 100%;
  padding: 11px;
  background: var(--rd);
  border: none;
  border-radius: var(--radius-button);
  color: #fff;
  font: 500 .82rem 'Noto Sans SC', sans-serif;
  cursor: pointer;
  letter-spacing: .06em;
  margin-top: 6px;
  transition: opacity .2s;
}
.start-quiz-btn:hover { opacity: .85; }
.start-quiz-btn:disabled { opacity: .4; cursor: not-allowed; }
.quiz-card {
  background: var(--sur);
  border: 1px solid var(--bd);
  border-radius: 10px;
  overflow: hidden;
  box-shadow: 0 4px 20px rgba(0,0,0,.08);
  animation: slideIn .25s ease;
}
@keyframes slideIn {
  from { opacity: 0; transform: translateY(10px); }
  to { opacity: 1; transform: translateY(0); }
}
.qc-progress {
  padding: 12px 18px;
  border-bottom: 1px solid var(--bd);
  display: flex;
  align-items: center;
  gap: 10px;
  background: var(--bg);
}
.qc-prog-bar {
  flex: 1;
  height: 4px;
  background: var(--bd);
  border-radius: 4px;
  overflow: hidden;
}
.qc-prog-fill {
  height: 100%;
  background: var(--rd);
  border-radius: 4px;
  transition: width .4s;
}
.qc-counter {
  font-size: .65rem;
  color: var(--mu);
  white-space: nowrap;
}
.qc-score {
  font-size: .65rem;
  color: var(--gn);
  font-weight: 500;
  white-space: nowrap;
}
.qc-body {
  padding: 26px 20px 18px;
}
.qc-type-badge {
  font-size: .58rem;
  letter-spacing: .12em;
  text-transform: uppercase;
  color: var(--mu);
  margin-bottom: 10px;
}
.qc-question {
  font-family: 'Lora', serif;
  font-size: 1.55rem;
  font-weight: 700;
  color: var(--ink);
  margin-bottom: 5px;
  line-height: 1.2;
}
.qc-question.zh {
  font-family: 'Noto Sans SC', sans-serif;
  font-size: 1.05rem;
  font-weight: 500;
}
.qc-phonetic {
  font-family: 'JetBrains Mono', monospace;
  font-size: .72rem;
  color: var(--mu);
  margin-bottom: 18px;
  display: flex;
  align-items: center;
  gap: 8px;
}
.qc-speak {
  background: none;
  border: 1px solid var(--bd);
  border-radius: 50%;
  width: 24px;
  height: 24px;
  cursor: pointer;
  font-size: .7rem;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: all .15s;
  flex-shrink: 0;
}
.qc-speak:hover { background: var(--rds); border-color: var(--rd); }
.qc-options {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 10px;
}
.qopt {
  padding: 12px 13px;
  border: 1px solid var(--bd);
  border-radius: 8px;
  background: var(--bg);
  cursor: pointer;
  font: 300 .8rem 'Noto Sans SC', sans-serif;
  color: var(--ink);
  text-align: left;
  transition: all .18s;
  line-height: 1.4;
  position: relative;
}
.qopt:hover:not(:disabled) { border-color: var(--bl); background: var(--bls); color: var(--bl); }
.qopt.correct { border-color: var(--gn) !important; background: var(--gns) !important; color: var(--gn) !important; font-weight: 500; }
.qopt.wrong { border-color: var(--rd) !important; background: var(--rds) !important; color: var(--rd) !important; }
.qopt:disabled { cursor: default; }
.qopt-mark {
  position: absolute;
  right: 10px;
  top: 50%;
  transform: translateY(-50%);
  font-size: .85rem;
}
.qc-feedback {
  padding: 14px 20px;
  border-top: 1px solid var(--bd);
  background: var(--bg);
  display: none;
}
.qc-feedback.show {
  display: block;
  animation: fadeIn .2s ease;
}
@keyframes fadeIn {
  from { opacity: 0; }
  to { opacity: 1; }
}
.qf-result {
  font-size: .82rem;
  font-weight: 500;
  margin-bottom: 5px;
}
.qf-correct { color: var(--gn); }
.qf-wrong { color: var(--rd); }
.qf-answer {
  font-size: .74rem;
  color: var(--mu);
  margin-bottom: 8px;
}
.qf-conf {
  font-size: .7rem;
  color: var(--am);
  background: var(--ams);
  padding: 6px 10px;
  border-radius: 4px;
  margin-bottom: 10px;
}
.next-btn {
  padding: 8px 22px;
  background: var(--ink);
  border: none;
  border-radius: 4px;
  color: #fff;
  font: 500 .75rem 'Noto Sans SC', sans-serif;
  cursor: pointer;
  transition: opacity .2s;
}
.next-btn:hover { opacity: .8; }
.quiz-result {
  background: var(--sur);
  border: 1px solid var(--bd);
  border-radius: 10px;
  padding: 36px 22px;
  text-align: center;
  box-shadow: 0 4px 20px rgba(0,0,0,.08);
}
.qr-emoji {
  font-size: 3rem;
  margin-bottom: 12px;
}
.qr-title {
  font-family: 'Lora', serif;
  font-size: 1.2rem;
  font-weight: 700;
  margin-bottom: 5px;
}
.qr-sub {
  font-size: .78rem;
  color: var(--mu);
  margin-bottom: 22px;
}
.qr-stats {
  display: grid;
  grid-template-columns: repeat(3,1fr);
  gap: 10px;
  margin-bottom: 22px;
}
.qrs {
  background: var(--bg);
  border: 1px solid var(--bd);
  border-radius: 6px;
  padding: 14px 8px;
  text-align: center;
}
.qrs-n {
  font-family: 'Lora', serif;
  font-size: 1.4rem;
  font-weight: 700;
}
.qrs-n.g { color: var(--gn); }
.qrs-n.r { color: var(--rd); }
.qrs-n.b { color: var(--bl); }
.qrs-l {
  font-size: .58rem;
  color: var(--mu);
  letter-spacing: .06em;
  text-transform: uppercase;
  margin-top: 2px;
}
.qr-btns {
  display: flex;
  gap: 10px;
  justify-content: center;
  flex-wrap: wrap;
}
.qr-btn {
  padding: 9px 20px;
  border-radius: var(--radius-button);
  border: 1px solid var(--bd);
  background: var(--bg);
  font: 400 .78rem 'Noto Sans SC', sans-serif;
  cursor: pointer;
  color: var(--ink);
  transition: all .15s;
}
.qr-btn:hover { border-color: var(--rd); color: var(--rd); }
.qr-btn.primary { background: var(--rd); border-color: var(--rd); color: #fff; }
.qr-btn.primary:hover { opacity: .85; }
.wrong-list {
  margin-top: 18px;
  text-align: left;
}
.wl-title {
  font-size: .65rem;
  letter-spacing: .1em;
  text-transform: uppercase;
  color: var(--mu);
  margin-bottom: 10px;
  display: flex;
  align-items: center;
  gap: 6px;
}
.wl-title::after {
  content: '';
  flex: 1;
  height: 1px;
  background: var(--bd);
}
.wrong-item {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  padding: 7px 0;
  border-bottom: 1px solid var(--bd);
  font-size: .76rem;
}
.wrong-item:last-child { border-bottom: none; }
.wi-word {
  font-family: 'Lora', serif;
  font-weight: 700;
  color: var(--rd);
}
.wi-ans {
  color: var(--mu);
  font-size: .7rem;
  text-align: right;
}
.prog-wrap {
  max-width: 680px;
  margin: 0 auto;
  padding: 24px 16px 60px;
}
.prog-summary {
  display: grid;
  grid-template-columns: repeat(3,1fr);
  gap: 12px;
  margin-bottom: 18px;
}
.ps-card {
  background: var(--sur);
  border: 1px solid var(--bd);
  border-radius: 8px;
  padding: 16px 12px;
  text-align: center;
}
.ps-n {
  font-family: 'Lora', serif;
  font-size: 1.7rem;
  font-weight: 700;
}
.ps-n.g { color: var(--gn); }
.ps-n.r { color: var(--rd); }
.ps-n.b { color: var(--bl); }
.ps-l {
  font-size: .58rem;
  color: var(--mu);
  letter-spacing: .08em;
  text-transform: uppercase;
  margin-top: 4px;
}
.prog-section {
  background: var(--sur);
  border: 1px solid var(--bd);
  border-radius: 8px;
  overflow: hidden;
  margin-bottom: 12px;
}
.prog-sec-head {
  padding: 11px 15px;
  border-bottom: 1px solid var(--bd);
  display: flex;
  align-items: center;
  justify-content: space-between;
  background: var(--bg);
}
.psh-title {
  font-size: .72rem;
  font-weight: 500;
  color: var(--ink2);
  display: flex;
  align-items: center;
  gap: 7px;
}
.psh-title::before {
  content: '';
  display: block;
  width: 3px;
  height: 11px;
  background: var(--rd);
  border-radius: 2px;
}
.psh-count {
  font-size: .62rem;
  color: var(--mu);
  background: var(--bd);
  padding: 1px 8px;
  border-radius: 20px;
}
.prog-word-list {
  padding: 8px 15px;
}
.prog-word-item {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 8px 0;
  border-bottom: 1px solid var(--bd);
  gap: 8px;
}
.prog-word-item:last-child { border-bottom: none; }
.pwi-left {
  display: flex;
  align-items: baseline;
  gap: 8px;
  flex: 1;
  min-width: 0;
}
.pwi-word {
  font-family: 'Lora', serif;
  font-size: .92rem;
  font-weight: 700;
  color: var(--ink);
}
.pwi-meaning {
  font-size: .68rem;
  color: var(--mu);
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}
.pwi-right {
  display: flex;
  align-items: center;
  gap: 6px;
  flex-shrink: 0;
}
.pwi-status {
  font-size: .58rem;
  padding: 2px 7px;
  border-radius: 20px;
}
.st-mastered { background: var(--gns); color: var(--gn); }
.st-learning { background: var(--ams); color: var(--am); }
.prog-reset-btn {
  width: 100%;
  padding: 9px;
  background: none;
  border: 1px solid var(--bd);
  border-radius: 4px;
  font: 300 .72rem 'Noto Sans SC', sans-serif;
  color: var(--mu);
  cursor: pointer;
  margin-top: 12px;
  transition: all .15s;
}
.prog-reset-btn:hover { border-color: var(--rd); color: var(--rd); }
@media (max-width:480px) {
  .qc-options { grid-template-columns: 1fr; }
  .qr-stats, .prog-summary { grid-template-columns: repeat(3,1fr); }
}
.qs-header {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  margin-bottom: 18px;
}
.qs-title {
  font-family: 'Lora', serif;
  font-size: .95rem;
  font-weight: 700;
  color: var(--ink);
}
.qs-hint {
  font-size: .62rem;
  color: var(--mu);
}
.qs-section {
  margin-bottom: 16px;
  padding-bottom: 16px;
  border-bottom: 1px solid var(--bd);
}
.qs-section:last-of-type { border-bottom: none; margin-bottom: 8px; }
.qs-sec-label {
  font-size: .68rem;
  font-weight: 500;
  color: var(--ink2);
  margin-bottom: 8px;
  letter-spacing: .02em;
}
.qs-sec-hint {
  font-size: .6rem;
  color: var(--mu);
  font-weight: 300;
}
.qs-row {
  display: flex;
  gap: 7px;
  flex-wrap: wrap;
}
.qbtn {
  padding: 5px 13px;
  border: 1.5px solid var(--bd);
  background: var(--bg);
  border-radius: 20px;
  font: 300 .68rem 'Noto Sans SC', sans-serif;
  color: var(--mu);
  cursor: pointer;
  transition: all .15s;
  white-space: nowrap;
  display: inline-flex;
  align-items: center;
  gap: 4px;
}
.qbtn:hover { border-color: var(--rd); color: var(--rd); }
.qbtn.on { background: var(--rd); border-color: var(--rd); color: #fff; }
.qbtn-count {
  font-size: .58rem;
  opacity: .75;
  font-family: 'JetBrains Mono', monospace;
}
.qbtn-cefr { font-weight: 500; }
.qbtn-a1.on { background: #2a6e46; border-color: #2a6e46; }
.qbtn-a2.on { background: #1e5ea0; border-color: #1e5ea0; }
.qbtn-b1.on { background: #6040a0; border-color: #6040a0; }
.qbtn-b2.on { background: #b83a2a; border-color: #b83a2a; }
.qbtn-c.on { background: #885c10; border-color: #885c10; }
.qs-meta {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 10px 0 14px;
  font-size: .7rem;
  color: var(--mu);
}
.qs-clear-btn {
  background: none;
  border: 1px solid var(--bd);
  border-radius: 4px;
  padding: 4px 10px;
  font: 300 .65rem 'Noto Sans SC', sans-serif;
  color: var(--mu);
  cursor: pointer;
  transition: all .15s;
}
.qs-clear-btn:hover { border-color: var(--rd); color: var(--rd); }
.quiz-settings {
  background: var(--sur);
  border: 1px solid var(--bd);
  border-radius: 10px;
  padding: 20px 20px 16px;
  margin-bottom: 20px;
}
.cefr-chip {
  border: none !important;
  padding: 3px 9px !important;
  font-size: .6rem !important;
  font-weight: 600 !important;
  border-radius: 20px !important;
  letter-spacing: .06em;
}
.prog-summary2 {
  background: var(--sur);
  border: 1px solid var(--bd);
  border-radius: 10px;
  padding: 18px 20px;
  margin-bottom: 14px;
  display: flex;
  align-items: center;
  gap: 20px;
}
.ps2-total {
  display: flex;
  align-items: center;
  gap: 14px;
  flex-shrink: 0;
}
.ps2-ring {
  position: relative;
  width: 72px;
  height: 72px;
  flex-shrink: 0;
}
.ps2-ring svg {
  width: 72px;
  height: 72px;
  transform: rotate(-90deg);
}
.ps2-pct {
  position: absolute;
  inset: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  font-family: 'Lora', serif;
  font-size: .95rem;
  font-weight: 700;
  color: var(--ink);
}
.ps2-labels {
  display: flex;
  flex-direction: column;
  gap: 3px;
}
.ps2-title {
  font-size: .72rem;
  font-weight: 500;
  color: var(--ink);
}
.ps2-sub {
  font-size: .65rem;
  color: var(--mu);
}
.ps2-stats {
  flex: 1;
  display: flex;
  gap: 0;
  border-left: 1px solid var(--bd);
  padding-left: 20px;
  flex-wrap: wrap;
}
.ps2-stat {
  flex: 1;
  text-align: center;
  padding: 6px 8px;
  min-width: 64px;
}
.ps2-n {
  display: block;
  font-family: 'Lora', serif;
  font-size: 1.4rem;
  font-weight: 700;
  line-height: 1;
}
.ps2-n.g { color: var(--gn); }
.ps2-n.b { color: var(--bl); }
.ps2-n.mu { color: var(--mu); }
.ps2-l {
  display: block;
  font-size: .58rem;
  color: var(--mu);
  letter-spacing: .06em;
  text-transform: uppercase;
  margin-top: 3px;
}
.prog-tabs {
  display: flex;
  gap: 6px;
  margin-bottom: 12px;
  flex-wrap: wrap;
}
.prog-tab {
  padding: 5px 14px;
  border: 1px solid var(--bd);
  background: var(--sur);
  border-radius: 20px;
  font: 300 .68rem 'Noto Sans SC', sans-serif;
  color: var(--mu);
  cursor: pointer;
  transition: all .15s;
}
.prog-tab:hover { border-color: var(--rd); color: var(--rd); }
.prog-tab.on { background: var(--rd); border-color: var(--rd); color: #fff; font-weight: 500; }
.pg-groups {
  display: flex;
  flex-direction: column;
  gap: 8px;
  margin-bottom: 14px;
}
.pg-group {
  background: var(--sur);
  border: 1px solid var(--bd);
  border-radius: 8px;
  overflow: hidden;
}
.pg-group-head {
  padding: 12px 15px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  cursor: pointer;
  transition: background .15s;
  user-select: none;
}
.pg-group-head:hover { background: var(--bg); }
.pg-group-left {
  display: flex;
  align-items: center;
  gap: 9px;
  min-width: 0;
}
.pg-group-dot {
  width: 9px;
  height: 9px;
  border-radius: 50%;
  flex-shrink: 0;
}
.pg-group-label {
  font-size: .78rem;
  font-weight: 500;
  color: var(--ink);
  white-space: nowrap;
}
.pg-group-sub {
  font-size: .62rem;
  color: var(--mu);
  white-space: nowrap;
}
.pg-group-right {
  display: flex;
  align-items: center;
  gap: 9px;
  flex-shrink: 0;
}
.pg-mini-bar {
  width: 80px;
  height: 5px;
  background: var(--bd);
  border-radius: 10px;
  overflow: hidden;
}
.pg-mini-fill {
  height: 100%;
  border-radius: 10px;
  transition: width .4s ease;
}
.pg-group-pct {
  font-size: .68rem;
  font-weight: 500;
  color: var(--ink);
  min-width: 28px;
  text-align: right;
}
.pg-arrow {
  font-size: .6rem;
  color: var(--mu);
  transition: transform .25s;
}
.pg-arrow.open { transform: rotate(180deg); color: var(--rd); }
.pg-group-body {
  display: none;
  border-top: 1px solid var(--bd);
}
.pg-group-body.open { display: block; }
.pwi2 {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 8px 15px;
  border-bottom: 1px solid var(--bd);
  gap: 8px;
}
.pwi2:last-child { border-bottom: none; }
.pwi2-left {
  display: flex;
  align-items: baseline;
  gap: 8px;
  flex: 1;
  min-width: 0;
}
.pwi2-word {
  font-family: 'Lora', serif;
  font-size: .88rem;
  font-weight: 700;
  color: var(--ink);
  white-space: nowrap;
}
.pwi2-meaning {
  font-size: .68rem;
  color: var(--mu);
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}
.pwi2-right {
  display: flex;
  align-items: center;
  gap: 7px;
  flex-shrink: 0;
}
.pwi2-acc {
  font-family: 'JetBrains Mono', monospace;
  font-size: .62rem;
  color: var(--mu);
}
.pwi2-toggle {
  width: 24px;
  height: 24px;
  border-radius: 50%;
  border: 1.5px solid var(--bd);
  background: none;
  cursor: pointer;
  font-size: .72rem;
  color: var(--mu);
  display: flex;
  align-items: center;
  justify-content: center;
  transition: all .15s;
  flex-shrink: 0;
}
.pwi2-toggle:hover { border-color: var(--gn); color: var(--gn); }
.pwi2-toggle.mastered { background: var(--gns); border-color: var(--gn); color: var(--gn); }
.ws-badge {
  font-size: .56rem;
  padding: 2px 7px;
  border-radius: 20px;
  white-space: nowrap;
  font-weight: 500;
}
.ws-mastered { background: var(--gns); color: var(--gn); }
.ws-practiced { background: var(--bls); color: var(--bl); }
.ws-new { background: var(--bd); color: var(--mu); }
@media (max-width:480px) {
  .prog-summary2 { flex-direction: column; align-items: flex-start; }
  .ps2-stats { border-left: none; padding-left: 0; border-top: 1px solid var(--bd); padding-top: 12px; width: 100%; }
  .pg-mini-bar { width: 50px; }
  .pg-group-sub { display: none; }
}
.wb-empty {
  text-align: center;
  padding: 60px 20px;
  color: var(--mu);
}
.wb-empty-icon {
  font-size: 3rem;
  margin-bottom: 16px;
}
.wb-list {
  padding: 0 16px 80px 16px;
  display: grid;
  gap: 12px;
}
.wb-item-left { flex: 1; }
.wb-item-word {
  font-size: 1.1rem;
  font-weight: 600;
  color: var(--ink);
  margin-bottom: 4px;
}
.wb-item-meaning {
  font-size: .85rem;
  color: var(--mu);
}
.wb-item-meta {
  font-size: .75rem;
  color: var(--mu);
  margin-top: 6px;
}
.wb-item-right {
  display: flex;
  gap: 8px;
}
.wb-remove-btn {
  padding: 6px 12px;
  border: 1px solid var(--rd);
  background: transparent;
  color: var(--rd);
  border-radius: 4px;
  cursor: pointer;
  font-size: .8rem;
}
.wb-remove-btn:hover { background: var(--rd); color: #fff; }
.wb-header {
  background: #fff;
  padding: 24px 20px;
  border-bottom: 1px solid var(--bd);
  margin-bottom: 20px;
}
.wb-title {
  font-family: "Noto Serif SC", serif;
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--ink);
  margin-bottom: 16px;
  display: flex;
  align-items: center;
  justify-content: space-between;
}
.wb-stats-row {
  display: flex;
  gap: 12px;
  margin-bottom: 20px;
}
.wb-stat-card {
  flex: 1;
  background: var(--bg);
  padding: 12px;
  border-radius: 8px;
  text-align: center;
  border: 1px solid transparent;
  transition: all 0.2s;
  cursor: pointer;
}
.wb-stat-card.active {
  background: #fff;
  border-color: var(--rd);
  box-shadow: 0 4px 12px rgba(192,57,43,0.15);
}
.wb-stat-num {
  font-size: 1.2rem;
  font-weight: 700;
  color: var(--ink);
}
.wb-stat-label {
  font-size: 0.75rem;
  color: var(--mu);
  margin-top: 4px;
}
.wb-count {
  font-size: .85rem;
  color: var(--mu);
}
.wb-filters {
  display: flex;
  gap: 8px;
  overflow-x: auto;
  padding-bottom: 4px;
}
.wb-filter-btn {
  padding: 6px 16px;
  border-radius: 20px;
  border: 1px solid var(--bd);
  background: #fff;
  color: var(--mu);
  font-size: 0.85rem;
  cursor: pointer;
  white-space: nowrap;
  transition: all 0.2s;
}
.wb-filter-btn.on { background: var(--rd); color: #fff; border-color: var(--rd); font-weight: 500; }
.wb-filter-btn:hover { border-color: var(--rd); }
.wb-card {
  background: var(--sur);
  border: 1px solid var(--bd);
  border-radius: var(--radius-card);
  padding: 16px;
  box-shadow: var(--shadow-card);
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  transition: box-shadow .2s, transform .2s;
  cursor: pointer;
  position: relative;
  overflow: hidden;
}
.wb-card:hover {
  box-shadow: 0 4px 18px rgba(0,0,0,.1);
  transform: translateY(-1px);
}
.wb-info {
  flex: 1;
  padding-left: 8px;
}
.wb-word-row {
  display: flex;
  align-items: baseline;
  gap: 8px;
  margin-bottom: 4px;
}
.wb-word {
  font-family: 'Lora', serif;
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--ink);
}
.wb-phonetic {
  font-family: 'JetBrains Mono', monospace;
  font-size: 0.7rem;
  color: var(--mu);
}
.wb-meaning {
  font-size: 0.85rem;
  color: var(--ink2);
  line-height: 1.4;
  margin-bottom: 8px;
}
.wb-meta {
  display: flex;
  gap: 8px;
  font-size: 0.75rem;
  color: var(--mu);
  align-items: center;
}
.wb-badge {
  padding: 2px 6px;
  border-radius: 4px;
  background: var(--bg);
  border: 1px solid var(--bd);
  color: var(--mu);
}
.wb-actions {
  display: flex;
  flex-direction: column;
  gap: 8px;
  padding-left: 12px;
  border-left: 1px dashed var(--bd);
  flex-shrink: 0;
}
.wb-btn {
  width: 32px;
  height: 32px;
  border-radius: 50%;
  border: 1px solid var(--bd);
  background: var(--bg);
  color: var(--mu);
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  font-size: 0.9rem;
  transition: all 0.15s;
}
.wb-btn:hover { background: var(--rds); border-color: var(--rd); }
.wb-btn.sound:hover { background: var(--bls); border-color: var(--bl); }
.wb-btn.mastery.mastered { background: var(--gns); border-color: var(--gn); color: var(--gn); }
.wb-btn.delete:hover { background: var(--rds); border-color: var(--rd); color: var(--rd); }
.status-dot {
  width: 7px;
  height: 7px;
  border-radius: 50%;
  display: inline-block;
  margin-right: 6px;
}
.status-dot.new { background: #3498db; }
.status-dot.learning { background: #f1c40f; }
.status-dot.mastered { background: #27ae60; }
.global-stats {
  display: flex;
  gap: 12px;
  margin: 20px 16px;
}
.global-stat-card {
  flex: 1;
  background: var(--sur);
  border-radius: 12px;
  padding: 16px;
  text-align: center;
  box-shadow: 0 2px 8px rgba(0,0,0,0.04);
}
.global-stat-num {
  font-size: 1.6rem;
  font-weight: 700;
  color: var(--rd);
}
.global-stat-label {
  font-size: 0.75rem;
  color: var(--mu);
  margin-top: 4px;
}
.wordbook-card {
  flex: 0 0 auto;
  width: 140px;
  background: var(--sur);
  border-radius: 16px;
  padding: 16px;
  border: 2px solid transparent;
  transition: all 0.2s;
  cursor: pointer;
  position: relative;
}
.wordbook-card.active {
  border-color: var(--rd);
  background: #fff;
}
.wordbook-name {
  font-weight: 600;
  font-size: 1rem;
  margin-bottom: 4px;
  padding-right: 30px;
}
.wordbook-count {
  font-size: 0.8rem;
  color: var(--mu);
}
.wordbook-edit, .wordbook-delete {
  position: absolute;
  top: 8px;
  width: 24px;
  height: 24px;
  border-radius: 50%;
  background: var(--bg);
  border: 1px solid var(--bd);
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  font-size: 0.8rem;
  transition: all 0.2s;
}
.wordbook-edit { right: 32px; }
.wordbook-delete { right: 4px; }
.wordbook-edit:hover { background: var(--bls); border-color: var(--bl); }
.wordbook-delete:hover { background: var(--rds); border-color: var(--rd); }

.detail-modal {
  display: none;
  position: fixed;
  inset: 0;
  background: rgba(0,0,0,0.5);
  z-index: 1000;
  align-items: center;
  justify-content: center;
  backdrop-filter: blur(4px);
}
.detail-modal.show { display: flex; }
.detail-content {
  background: var(--sur);
  border-radius: 12px;
  width: 90%;
  max-width: 700px;
  max-height: 80vh;
  overflow-y: auto;
  padding: 24px;
  position: relative;
  box-shadow: 0 10px 40px rgba(0,0,0,0.2);
  animation: fadeIn 0.2s;
}
.detail-close {
  position: absolute;
  top: 16px;
  right: 16px;
  width: 32px;
  height: 32px;
  border-radius: 50%;
  border: none;
  background: var(--bg);
  font-size: 1.2rem;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--mu);
}
.detail-close:hover { background: var(--rds); color: var(--rd); }
.mistake-card {
  background: var(--rds);
  border: 1px solid var(--rd);
  border-radius: 8px;
  padding: 12px;
  margin-bottom: 12px;
}
.mistake-card:last-child { margin-bottom: 0; }
.mistake-row {
  display: flex;
  align-items: baseline;
  gap: 8px;
  margin-bottom: 6px;
}
.mistake-row .wrong {
  color: var(--rd);
  font-weight: 500;
}
.mistake-row .right {
  color: var(--gn);
  font-weight: 500;
}
.mistake-reason {
  font-size: 0.7rem;
  color: var(--mu);
  font-style: italic;
  padding-left: 22px;
}
.exam-card {
  background: var(--pus);
  border: 1px solid var(--pu);
  border-radius: 8px;
  padding: 12px;
  margin-bottom: 12px;
}
.exam-card:last-child { margin-bottom: 0; }
.exam-question {
  font-family: 'Lora', serif;
  font-size: 0.85rem;
  color: var(--ink);
  line-height: 1.5;
  margin-bottom: 6px;
}
.exam-options {
  font-family: 'JetBrains Mono', monospace;
  font-size: 0.7rem;
  color: var(--mu);
  margin-bottom: 6px;
}
.exam-answer {
  color: var(--gn);
  font-weight: 500;
  margin-bottom: 4px;
}
.exam-analysis {
  font-size: 0.65rem;
  color: var(--mu);
}
.exam-sentence { margin-top: 8px; }
.syn-grid {
  display: grid;
  grid-template-columns: 1fr 2fr;
  gap: 0;
}
.syn-item { display: contents; }
.syn-word {
  font-weight: 600;
  color: var(--ink);
  padding: 8px 0;
  border-bottom: 1px solid var(--bd);
  font-size: 0.78rem;
}
.syn-diff {
  color: var(--mu);
  font-size: 0.75rem;
  line-height: 1.5;
  padding: 8px 0;
  border-bottom: 1px solid var(--bd);
}
.syn-item:last-child .syn-word,
.syn-item:last-child .syn-diff { border-bottom: none; }
.family-grid {
  display: grid;
  grid-template-columns: 1.2fr 0.8fr 2fr;
  gap: 0;
}
.family-item { display: contents; }
.family-word {
  font-weight: 600;
  color: var(--ink);
  padding: 8px 0;
  border-bottom: 1px solid var(--bd);
  font-size: 0.78rem;
}
.family-pos {
  font-family: 'JetBrains Mono', monospace;
  font-size: 0.62rem;
  color: var(--mu);
  padding: 8px 0;
  border-bottom: 1px solid var(--bd);
}
.family-zh {
  color: var(--ink2);
  font-size: 0.75rem;
  padding: 8px 0;
  border-bottom: 1px solid var(--bd);
}
.family-item:last-child .family-word,
.family-item:last-child .family-pos,
.family-item:last-child .family-zh { border-bottom: none; }
.spell-input-area {
  display: flex;
  gap: 8px;
  margin: 16px 0 8px;
}
.spell-input-area input {
  flex: 1;
  padding: 12px;
  border: 1px solid var(--bd);
  border-radius: 6px;
  background: var(--sur);
  color: var(--ink);
  font-size: 1rem;
  outline: none;
}
.spell-input-area input:focus { border-color: var(--rd); }
.spell-input-area button {
  padding: 0 20px;
  background: var(--rd);
  color: #fff;
  border: none;
  border-radius: 6px;
  font-weight: 500;
  cursor: pointer;
  transition: opacity 0.2s;
}
.spell-input-area button:hover { opacity: 0.85; }
.accent-bar {
  display: flex;
  gap: 6px;
  flex-wrap: wrap;
  margin: 8px 0 16px;
}
.accent-bar button {
  width: 40px;
  height: 40px;
  border: 1px solid var(--bd);
  background: var(--sur);
  color: var(--ink);
  border-radius: 6px;
  font-size: 1rem;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.15s;
}
.accent-bar button:hover { background: var(--bls); border-color: var(--bl); }
@media (max-width:600px) {
  .accent-bar button { width: 36px; height: 36px; font-size: 0.9rem; }
}
.qc-hint {
  background: var(--bg);
  border: 1px solid var(--bd);
  border-radius: 50%;
  width: 24px;
  height: 24px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  font-size: 0.8rem;
  color: var(--mu);
}
.qc-hint:hover { background: var(--bls); border-color: var(--bl); }
.qc-pos {
  font-family: 'JetBrains Mono', monospace;
  font-size: 0.7rem;
  color: var(--mu);
  margin-bottom: 12px;
  padding: 2px 8px;
  background: var(--bg);
  display: inline-block;
  border-radius: 4px;
}
.show-answer-btn {
  background: var(--bg);
  border: 1px solid var(--bd);
  border-radius: 6px;
  padding: 6px 12px;
  margin-left: 8px;
  font-size: 0.8rem;
  cursor: pointer;
  color: var(--mu);
}
.show-answer-btn:hover { background: var(--bls); border-color: var(--bl); }
.strict-mode-checkbox {
  margin: 0 8px;
  vertical-align: middle;
}
.conj-tenses-section, .conj-persons-section { margin-bottom: 16px; }
.conj-tenses-grid, .conj-persons-grid {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
}
.conj-btn {
  padding: 4px 10px;
  border: 1px solid var(--bd);
  background: var(--bg);
  border-radius: 20px;
  font: 300 0.65rem 'Noto Sans SC', sans-serif;
  color: var(--mu);
  cursor: pointer;
  white-space: nowrap;
  transition: all 0.15s;
}
.conj-btn.on { background: var(--rd); border-color: var(--rd); color: #fff; }
.conj-input-area {
  display: flex;
  gap: 8px;
  margin: 16px 0 8px;
  flex-wrap: wrap;
}
.conj-input-area input {
  flex: 1 1 200px;
  padding: 12px;
  border: 1px solid var(--bd);
  border-radius: 6px;
  background: var(--sur);
  color: var(--ink);
  font-size: 1rem;
  outline: none;
}
.conj-input-area input:focus { border-color: var(--rd); }
.conj-input-area button {
  padding: 0 20px;
  background: var(--rd);
  color: #fff;
  border: none;
  border-radius: 6px;
  font-weight: 500;
  cursor: pointer;
  transition: opacity 0.2s;
}
.conj-two-inputs {
  display: flex;
  gap: 8px;
  width: 100%;
}
.conj-two-inputs input { flex: 1; }
@media (max-width:600px) { .conj-input-area { flex-direction: column; } }

.chart-container {
  margin-top: 12px;
  height: 140px;
  position: relative;
  cursor: pointer;
}
.chart-container canvas {
  width: 100%;
  height: 100%;
  display: block;
}
.ring-chart {
  width: 100px;
  height: 100px;
  margin: 0 auto;
}
.mastered-badge {
  display: inline-block;
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--gn);
  margin-right: 4px;
}
.word-rank-word:hover { color: var(--rd); }
.word-rank-count {
  font-family: 'JetBrains Mono', monospace;
  font-size: 0.7rem;
  color: var(--mu);
  background: var(--bg);
  padding: 2px 8px;
  border-radius: 12px;
}
.word-rank-buttons {
  display: flex;
  gap: 4px;
  flex-shrink: 0;
}
.word-rank-buttons .wb-btn {
  width: 24px !important;
  height: 24px !important;
  font-size: 0.75rem !important;
  line-height: 1 !important;
  border-radius: 50%;
  padding: 0;
  display: inline-flex;
  align-items: center;
  justify-content: center;
}
.recent-mastered-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(120px, 1fr));
  gap: 8px;
  margin-top: 12px;
}
.recent-mastered-card {
  background: var(--bg);
  border: 1px solid var(--bd);
  border-radius: 6px;
  padding: 8px;
  cursor: pointer;
  transition: all 0.15s;
}
.recent-mastered-card:hover { border-color: var(--rd); background: var(--rds); }
.recent-mastered-word {
  font-family: 'Lora', serif;
  font-size: 0.9rem;
  font-weight: 600;
  color: var(--ink);
}
.recent-mastered-mean {
  font-size: 0.7rem;
  color: var(--mu);
  margin-top: 2px;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

#calendarCard table {
  table-layout: fixed !important;
  width: 100% !important;
  border-collapse: collapse !important;
}
#calendarCard td {
  text-align: center !important;
  padding: 4px 0 !important;
  font-size: 0.65rem !important;
  white-space: nowrap !important;
  overflow: hidden !important;
}
#calendarCard .calendar-day {
  width: 24px !important;
  height: 24px !important;
  line-height: 24px !important;
  border-radius: 50% !important;
}
.user-avatar {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  transition: background 0.2s;
}
.user-avatar:hover { background: var(--rd) !important; }
@media (max-width:600px) {
  .sb2, .fav-btn, .fb, .vb, .qbtn, .icon-btn,
  .start-quiz-btn, .qs-clear-btn, .qopt, .quiz-back-btn,
  .qc-speak, .qc-hint, .show-answer-btn, .next-btn,
  .accent-bar button, .spell-input-area button {
    min-width: 44px;
    min-height: 44px;
    display: inline-flex;
    align-items: center;
    justify-content: center;
  }
  /* 手机端朗读是独立操作，保留 44px 触控面积。 */
  .speak-btn {
    min-width: 44px !important;
    min-height: 44px !important;
    width: 44px;
    height: 44px;
    font-size: 0.9rem;
  }
}
  .wd { font-size: 1.2rem; }
  .irv { font-size: 0.75rem; }
  .frow { padding-left: 10px; padding-right: 10px; gap: 8px; }
  .wl.gv { columns: 1 !important; }
  .calendar-table td { font-size: 0.7rem; }
@media (max-width:480px) {
  .syn-grid { grid-template-columns: 1fr; }
  .syn-word { border-bottom: none; padding-bottom: 2px; }
  .syn-diff { padding-top: 0; margin-bottom: 8px; }
  .family-grid { grid-template-columns: 1fr; }
  .family-word, .family-pos, .family-zh { border-bottom: none; padding: 2px 0; }
}
@keyframes slideIn {
  from { transform: translateX(100%); opacity: 0; }
  to { transform: translateX(0); opacity: 1; }
}
/* 手机横屏 & 小平板竖屏 (481px - 767px) */
@media (min-width: 481px) and (max-width: 767px) {
  /* 后续需要在这里添加样式 */
}

/* 平板竖屏 (768px - 1023px) */
@media (min-width: 768px) and (max-width: 1023px) {
   .hero::before {
    font-size: 4rem;
  }
  .stats {
    flex-wrap: wrap;
    justify-content: space-around;
  }
  .stat {
    width: 45%;
    border-right: none;
    padding: 8px 0;
  }
  .stat:nth-child(2) {
    border-right: none; /* 确保第二个也没有右边框 */
  }
    .ct {
    padding: 10px 12px 8px;
  }
  .wd {
    font-size: 1.3rem;
  }
  .ph {
    font-size: 0.65rem;
  }
  .irv {
    font-size: 0.72rem;
  }
  .stat-card-progress,
  .stat-card-simple {
    min-height: 140px;
  }
  .wordbook-grid-simple {
  grid-template-columns: repeat(3, 1fr);
}
}
@media (min-width: 768px) and (max-width: 1023px) {
  .hero::before {
    font-size: 4rem;
  }
  .stats {
    flex-wrap: wrap;
    justify-content: space-around;
  }
  .stat {
    width: 45%;
    border-right: none;
    padding: 8px 0;
  }
  .stat:nth-child(2) {
    border-right: none; /* 确保第二个也没有右边框 */
  }
}
/* 平板横屏 / 小桌面 (1024px - 1279px) */
@media (min-width: 1024px) and (max-width: 1279px) {
  /* 后续需要在这里添加样式 */
}

/* 大桌面 (1280px 及以上) */
@media (min-width: 1280px) {
  .wl.gv {
    -webkit-columns: 3;
    -moz-columns: 3;
    columns: 3;
  }
}
/* ========== 抽屉样式 ========== */
.drawer-overlay {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: rgba(0,0,0,0.5);
  backdrop-filter: blur(4px);
  z-index: 200;
  opacity: 0;
  visibility: hidden;
  transition: opacity 0.3s, visibility 0.3s;
}
.drawer-overlay.show {
  opacity: 1;
  visibility: visible;
}
.drawer {
  position: fixed;
  top: 0;
  right: -320px;
  width: 300px;
  height: 100%;
  background: var(--sur);
  box-shadow: -2px 0 20px rgba(0,0,0,0.2);
  z-index: 300;
  transition: right 0.3s ease;
  display: flex;
  flex-direction: column;
  padding: 20px 16px;
  box-sizing: border-box;
}
.drawer.open { right: 0; }
body.dark .drawer {
  background: var(--sur);
  border-left: 1px solid var(--bd);
}
.drawer-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 24px;
}
.drawer-title {
  font-family: 'Lora', serif;
  font-size: 1.2rem;
  font-weight: 600;
  color: var(--ink);
}
.drawer-header .icon-btn {
  color: var(--mu);
}
.drawer-header .icon-btn:hover {
  background: var(--rds);
  color: var(--rd);
}
.drawer-content {
  flex: 1;
  display: flex;
  flex-direction: column;
  gap: 16px;
}
.drawer-user {
  padding: 12px 0;
  border-bottom: 1px solid var(--bd);
  margin-bottom: 8px;
}
.drawer-user .login-btn {
  width: 100%;
  padding: 12px;
  background: var(--rd);
  color: #fff;
  border: none;
  border-radius: 12px;
  font-size: 1rem;
  font-weight: 500;
  cursor: pointer;
  transition: opacity 0.2s;
}
.drawer-user .login-btn:hover { opacity: 0.85; }
.drawer-user .user-info {
  display: flex;
  align-items: center;
  gap: 12px;
}
.drawer-user .user-avatar-small {
  width: 44px;
  height: 44px;
  border-radius: 50%;
  background: var(--bl);
  color: #fff;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.2rem;
}
.drawer-user .user-details { flex: 1; }
.drawer-user .user-phone {
  font-weight: 500;
  color: var(--ink);
}
.drawer-user .logout-btn {
  background: transparent;
  border: 1px solid var(--bd);
  color: var(--mu);
  padding: 6px 12px;
  border-radius: 20px;
  font-size: 0.8rem;
  cursor: pointer;
  transition: all 0.15s;
}
.drawer-user .logout-btn:hover { border-color: var(--rd); color: var(--rd); }
.switch {
  position: relative;
  display: inline-block;
  width: 44px;
  height: 24px;
}
.switch input { opacity: 0; width: 0; height: 0; }
.slider {
  position: absolute;
  cursor: pointer;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background-color: var(--bd);
  transition: .3s;
  border-radius: 24px;
}
.slider:before {
  position: absolute;
  content: "";
  height: 20px;
  width: 20px;
  left: 2px;
  bottom: 2px;
  background-color: white;
  transition: .3s;
  border-radius: 50%;
}
input:checked + .slider { background-color: var(--rd); }
input:checked + .slider:before { transform: translateX(20px); }
.drawer-item {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 8px 0;
  color: var(--ink);
  font-size: 0.95rem;
}
.drawer-item a {
  color: var(--ink);
  text-decoration: none;
  width: 100%;
}
.drawer-item a:hover { color: var(--rd); }
.drawer-btn {
  width: 100%;
  padding: 12px;
  background: var(--rd);
  color: #fff;
  border: none;
  border-radius: 12px;
  font-size: 0.95rem;
  font-weight: 500;
  cursor: pointer;
  transition: opacity 0.2s;
}
.drawer-btn:hover { opacity: 0.85; }
/* 抽屉用户卡片 */
.drawer-user-card {
  padding: 16px 0;
  border-bottom: 1px solid var(--bd);
  margin-bottom: 16px;
  text-align: center;
}
.drawer-user-card .login-btn {
  width: 100%;
  padding: 12px;
  background: var(--rd);
  color: #fff;
  border: none;
  border-radius: 12px;
  font-size: 1rem;
  font-weight: 500;
  cursor: pointer;
  transition: opacity 0.2s;
}
.drawer-user-card .login-btn:hover { opacity: 0.85; }
.drawer-user-card .user-info {
  display: flex;
  align-items: center;
  gap: 12px;
}
.drawer-user-card .user-avatar {
  width: 48px;
  height: 48px;
  border-radius: 50%;
  background: var(--bl);
  color: #fff;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.5rem;
}
.drawer-user-card .user-details {
  flex: 1;
  text-align: left;
}
.drawer-user-card .user-name {
  font-weight: 600;
  font-size: 1rem;
  color: var(--ink);
}
.drawer-user-card .user-phone {
  font-size: 0.8rem;
  color: var(--mu);
}

/* 小按钮样式（用于解锁和退出） */
.drawer-btn-small {
  background: transparent;
  border: 1px solid var(--bd);
  color: var(--rd);
  padding: 6px 12px;
  border-radius: 20px;
  font-size: 0.8rem;
  cursor: pointer;
  transition: all 0.15s;
}
.drawer-btn-small:hover {
  background: var(--rds);
  border-color: var(--rd);
}
/* 进度条胶囊 - 新增 */
.progress-capsule {
  display: flex;
  align-items: center;
  gap: 10px;
  max-width: 300px;
  margin: 0 auto;
  background: #e4ddd4;
  border-radius: 20px;
  padding: 0 12px 0 0;
  height: 12px;
}
.progress-capsule .prog-bar {
  flex: 1;
  height: 12px;
  background: transparent;
  border-radius: 20px 0 0 20px;
  overflow: hidden;
}
.progress-capsule .prog-fill {
  height: 100%;
  background: var(--rd);
  border-radius: 20px 0 0 20px;
  transition: width .6s ease;
}
.progress-capsule .prog-pct {
  font-size: 0.8rem;
  color: var(--ink);
  font-weight: 500;
  min-width: 36px;
  text-align: right;
  line-height: 12px;
}
@media (min-width: 768px) {
  .progress-capsule {
    max-width: 400px;
  }
}

.capsule .count-badge {
  background: rgba(255,255,255,0.2);
  border-radius: 12px;
  padding: 2px 6px;
  font-size: 0.7rem;
  margin-left: 4px;
}

/* 下拉菜单 */
@keyframes fadeIn {
  from { opacity: 0; transform: translateY(-5px); }
  to { opacity: 1; transform: translateY(0); }
}

/* 已选条件胶囊条 */
.active-filters {
  display: flex;
  gap: 8px;
  flex-wrap: wrap;
  margin-top: 8px;
}
.active-filter {
  display: inline-flex;
  align-items: center;
  gap: 4px;
  padding: 4px 10px;
  background: var(--rds);
  border: 1px solid var(--rd);
  border-radius: 20px;
  font-size: 0.75rem;
  color: var(--rd);
}
.active-filter .remove {
  cursor: pointer;
  font-weight: bold;
  margin-left: 4px;
}
/* ========== 阶段5：底部悬浮导航（移动端） ========== */
.bottom-nav {
  position: fixed;
  bottom: 0;
  left: 0;
  width: 100%;
  height: 60px;
  background: rgba(255, 255, 255, 0.85);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  border-top: 1px solid rgba(0,0,0,0.05);
  box-shadow: 0 -2px 10px rgba(0,0,0,0.05);
  display: flex;
  justify-content: space-around;
  align-items: center;
  z-index: 100;
  display: none; /* 默认隐藏，仅在移动端显示 */
}
body.dark .bottom-nav {
  background: rgba(30, 30, 30, 0.85);
  border-top-color: rgba(255,255,255,0.05);
}
.nav-item {
  appearance: none;
  border: 0;
  background: transparent;
  padding: 0;
  font-family: inherit;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  flex: 1;
  height: 100%;
  color: var(--mu);
  font-size: 0.8rem;
  transition: color 0.2s;
  cursor: pointer;
}
.nav-item.active {
  color: var(--rd);
}
.nav-icon {
  font-size: 1.3rem;
  margin-bottom: 2px;
}
.nav-label {
  font-size: 0.7rem;
}

/* 移动端：显示底部导航，隐藏顶部标签，并调整页面底部内边距 */
@media (max-width: 1023px) {
  .page-tabs { display: none; }
  .bottom-nav { display: flex; }
  .main, .quiz-wrap { padding-bottom: 70px; }
}

@media (min-width: 1024px) {
  .page-tabs { display: flex; }  /* 确保显示顶部标签 */
  .bottom-nav { display: none; }
}
/* 收藏组容器 - 无绝对定位，作为 flex 项 */
.fav-container {
  position: relative;
  display: flex;
  align-items: center;
  border-radius: 30px;
  background: #f0f0f0;
  overflow: visible;  /* 原来是 hidden，改为 visible */
  box-shadow: 0 2px 6px rgba(0,0,0,0.08);
  transition: box-shadow 0.2s;
  height: 40px;
}
.fav-container:hover {
  box-shadow: 0 4px 12px rgba(0,0,0,0.12);
}
body.dark .fav-container {
  background: #2a2a2a;
  box-shadow: 0 2px 6px rgba(0,0,0,0.3);
}

/* 星星按钮 */
.fav-btn {
  width: 40px;
  height: 40px;
  border: none;
  background: transparent;
  color: #aaa;
  font-size: 1.3rem;
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  transition: all 0.2s;
}
.fav-btn.on {
  color: #ff9800;
  background: rgba(255,152,0,0.1);
}
.fav-btn:hover {
  transform: scale(1.1);
  background: rgba(255,152,0,0.15);
}
/* 下拉箭头按钮 */
.fav-dropdown-btn {
  width: 40px;
  height: 40px;
  border: none;
  background: transparent;
  color: #aaa;
  font-size: 0.8rem;
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  transition: background 0.2s;
  border-left: 1px solid rgba(0,0,0,0.05);
}
.fav-dropdown-btn:hover {
  background: rgba(0,0,0,0.05);
}
body.dark .fav-dropdown-btn {
  border-left-color: rgba(255,255,255,0.1);
}
body.dark .fav-dropdown-btn:hover {
  background: rgba(255,255,255,0.1);
}

/* 下拉菜单 */
.fav-dropdown-menu {
  position: absolute;
  z-index: 2000;          /* 添加这一行 */
  top: 100%;
  right: 0;
  background: var(--sur);
  border: 1px solid var(--bd);
  border-radius: 6px;
  box-shadow: var(--shadow-dropdown);
  min-width: 150px;
  padding: 4px 0;
  display: none;
}
.fav-dropdown-menu[style*="display: block"] {
  display: block !important; /* 确保内联样式生效 */
}
.fav-dropdown-item {
  padding: 8px 14px;
  cursor: pointer;
  font-size: 0.8rem;
  color: var(--ink);
  white-space: nowrap;
}
.fav-dropdown-item:hover { background: var(--rds); color: var(--rd); }


/* 详情按钮 - 统一背景 */
.detail-btn {
  width: 40px;
  height: 40px;
  border: none;
  background: #f0f0f0;
  color: var(--mu);
  font-size: 1.2rem;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  border-radius: 50%;
  transition: background 0.15s, color 0.15s;
  box-shadow: 0 2px 6px rgba(0,0,0,0.08);
}
.detail-btn:hover {
  background: var(--rds);
  color: var(--rd);
}
body.dark .detail-btn {
  background: #2a2a2a;
}
body.dark .detail-btn:hover {
  background: #3a1610;
  color: var(--rd);
}

/* 右上角按钮组容器 */
.ct-r {
  display: flex;
  align-items: center;
  gap: 8px;
  flex-shrink: 0;
  flex-wrap: wrap;        /* 允许换行 */
  justify-content: flex-end;
  max-width: 100%;        /* 限制最大宽度 */
}

/* 掌握按钮 */
.mastery-btn {
  width: 40px;
  height: 40px;
  border: none;
  background: #f0f0f0;
  color: var(--mu);
  font-size: 1.2rem;
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  border-radius: 50%;
  transition: all 0.2s;
  box-shadow: 0 2px 6px rgba(0,0,0,0.08);
}
.mastery-btn:hover {
  background: var(--rds);
  border-color: var(--rd);
  color: var(--rd);
}
.mastery-btn.on {
  background: var(--gns);
  color: var(--gn);
}
.mastery-btn.on:hover {
  background: #c8e6c9;
  color: #2e7d32;
}
body.dark .mastery-btn {
  background: #2a2a2a;
}
/* 遮罩层 */
.modal-overlay {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: rgba(0,0,0,0.5);
  backdrop-filter: blur(4px);
  z-index: 1000;
  opacity: 0;
  visibility: hidden;
  transition: opacity 0.3s, visibility 0.3s;
}
.modal-overlay.show {
  opacity: 1;
  visibility: visible;
}

/* 底部弹窗 */
.bottom-sheet {
  position: fixed;
  bottom: 0;
  left: 0;
  width: 100%;
  background: var(--sur);
  border-radius: 20px 20px 0 0;
  box-shadow: 0 -4px 20px rgba(0,0,0,0.15);
  z-index: 1001;
  transform: translateY(100%);
  transition: transform 0.3s ease;
  max-height: 80vh;
  display: flex;
  flex-direction: column;
}
.bottom-sheet.show {
  transform: translateY(0);
}
.bottom-sheet-header {
  padding: 16px 20px;
  border-bottom: 1px solid var(--bd);
  display: flex;
  justify-content: space-between;
  align-items: center;
}
.bottom-sheet-title {
  font-weight: 600;
  font-size: 1.1rem;
  color: var(--ink);
}
.bottom-sheet-close {
  width: 32px;
  height: 32px;
  border-radius: 50%;
  background: var(--bg);
  border: none;
  color: var(--mu);
  font-size: 1.2rem;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
}
.bottom-sheet-close:hover {
  background: var(--rds);
  color: var(--rd);
}
.bottom-sheet-content {
  padding: 16px 20px;
  overflow-y: auto;
  flex: 1;
}
.filter-option {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 14px 0;
  border-bottom: 1px solid var(--bd);
  cursor: pointer;
}
.filter-option:last-child {
  border-bottom: none;
}
.filter-option.selected {
  color: var(--rd);
  font-weight: 500;
}
.filter-option .option-count {
  color: var(--mu);
  font-size: 0.85rem;
  background: var(--bg);
  padding: 2px 8px;
  border-radius: 20px;
}
.filter-option.selected .option-count {
  background: rgba(255,255,255,0.2);
  color: #fff;
}
body.dark .filter-option.selected .option-count {
  background: rgba(255,255,255,0.2);
  color: #fff;
}
/* 词本卡片基础样式（两行网格布局 - 全局） */
.wordbook-card-simple {
  display: grid;
  grid-template-columns: auto 1fr auto;
  grid-template-rows: auto auto;
  align-items: center;
  gap: 4px 12px;
  padding: 12px;
  background: var(--sur);
  border-radius: 20px;
  box-shadow: var(--shadow-card);
  border: 1px solid var(--bd);
  cursor: pointer;
  transition: transform 0.2s ease, box-shadow 0.2s ease;
}
.wordbook-card-simple .card-icon {
  grid-row: 1;
  grid-column: 1;
  width: 36px;
  height: 36px;
  font-size: 1.2rem;
  margin: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: 12px;
  background: #e0eaf8; /* 保留原有图标背景色，实际颜色由具体类决定 */
}
.wordbook-card-simple .card-badge {
  grid-row: 1;
  grid-column: 3;
  position: static;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  background: var(--rd);
  color: white;
  font-size: 0.7rem;
  font-weight: 600;
  border-radius: 20px;
  padding: 2px 8px;
  min-width: 28px;
  text-align: center;
}
.wordbook-card-simple .card-title {
  grid-row: 2;
  grid-column: 1;
  font-size: 0.9rem;
  font-weight: 600;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
  margin: 0;
}
.wordbook-card-simple .card-wordcount {
  grid-row: 2;
  grid-column: 3;
  font-size: 0.8rem;
  color: var(--mu);
  text-align: right;
  margin: 0;
}
/* 新建词本卡片特殊处理（覆盖网格布局） */
.wordbook-card-simple.custom {
  display: flex;
  align-items: center;
  justify-content: center;
  flex-direction: column;
  gap: 6px;
  min-height: 90px;
  background: var(--sur);
  border: 1px solid var(--bd);
  border-radius: 20px;
  box-shadow: var(--shadow-card);
}
.wordbook-card-simple.custom .plus-icon {
  font-size: 1.8rem;
  margin: 0;
  color: var(--mu);
}
/* 复习按钮 */
.review-btn {
  width: 100%;
  background: var(--rd);
  border: none;
  border-radius: 30px;
  padding: 16px 20px;
  margin-bottom: 28px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  cursor: pointer;
  transition: transform 0.2s ease, box-shadow 0.2s ease;
  box-shadow: 0 10px 20px rgba(184,58,42,0.15);
  color: white;
  font-size: 1rem;
  font-weight: 500;
}
.review-btn:hover {
  transform: translateY(-2px);
  box-shadow: 0 15px 30px rgba(184,58,42,0.2);
}
.review-btn .arrow {
  width: 30px;
  height: 30px;
  background: rgba(255,255,255,0.2);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.2rem;
  transition: transform 0.2s;
}
.review-btn:hover .arrow {
  transform: translateX(4px);
}

/* 词本网格 */
.wordbook-grid-simple {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 12px;
  margin-bottom: 24px;
}

@media (min-width: 768px) {
  .wordbook-grid-simple {
    grid-template-columns: repeat(3, 1fr);
  }
   .filter-capsules,
  .active-filters {
    overflow-x: visible;
    flex-wrap: wrap;
  }
  .filter-capsules {
    flex-shrink: 1; /* 允许收缩 */
  }
  .filter-row {
    flex-wrap: wrap; /* 允许整行换行 */
  }
  .md {
    max-width: 400px;
    padding: 36px 32px;
  }
}
.card-icon {
  width: 40px;
  height: 40px;
  border-radius: 12px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.2rem;
  margin-bottom: 8px;
}
.card-icon.default { background: #e0eaf8; color: #1e5ea0; }
.card-icon.wrong { background: #faecea; color: #b83a2a; }
.card-icon.mastered { background: #e4f0e9; color: #2a6e46; }
.card-icon.custom { background: #f9f7f2; color: #7a7268; }
.card-title {
  font-family: 'Lora', serif;
  font-size: 1rem;
  font-weight: 600;
  color: var(--ink);
  margin-bottom: 2px;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}
.card-wordcount {
  font-size: 0.7rem;
  color: var(--mu);
}
.card-badge {
  position: absolute;
  top: 8px;
  right: 8px;
  background: var(--rd);
  color: white;
  border-radius: 30px;
  padding: 2px 6px;
  font-size: 0.6rem;
  font-weight: 600;
}

/* 词本详情 */
.wordbook-detail-simple {
  background: #ffffff;
  border-radius: 24px;
  padding: 20px;
  box-shadow: 0 10px 30px rgba(0,0,0,0.03);
}
.detail-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 16px;
  padding-bottom: 8px;
  border-bottom: 1px solid var(--bd);
}
.detail-title {
  font-family: 'Lora', serif;
  font-size: 1.1rem;
  font-weight: 600;
  color: var(--ink);
}
.detail-count {
  font-size: 0.8rem;
  color: var(--mu);
}
/* 空状态推荐词样式 */
.recommend-word-item {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 10px 0;
  border-bottom: 1px dashed var(--bd);
}
.recommend-word-item .word {
  font-family: 'Lora', serif;
  font-size: 0.95rem;
  font-weight: 500;
  color: var(--ink);
  cursor: pointer;
}
.recommend-word-item .meaning {
  font-size: 0.75rem;
  color: var(--mu);
  margin-left: 8px;
}
.recommend-word-item .add-btn {
  background: var(--rd);
  color: white;
  border: none;
  border-radius: 20px;
  padding: 4px 10px;
  font-size: 0.7rem;
  cursor: pointer;
  transition: opacity 0.2s;
}
.recommend-word-item .add-btn:hover {
  opacity: 0.8;
}
.empty-guide {
  text-align: center;
  padding: 20px;
  color: var(--mu);
}
.empty-guide p {
  margin-bottom: 12px;
}
@media (max-width: 480px) {
  /* 原有内容保持不变，在后面追加 */
  .tb {
    padding: 0 12px;
  }
  .logo {
    font-size: 0.95rem;
  }
  .logo sub {
    font-size: 0.6rem;
  }
}
@media (min-width: 1024px) {
  .quiz-wrap {
    max-width: 800px;
  }
  .qopt {
    padding: 14px 18px;
    font-size: 0.9rem;
  }
  .drawer {
    width: 360px;
    right: -360px;   /* 与宽度一致，完全移出视口 */
  }
}
/* 触摸反馈 */
.capsule:active,
.qbtn:active,
.fb:active,
.vb:active,
.sb2:active,
.detail-btn:active,
.mastery-btn:active,
.fav-btn:active,
.fav-dropdown-btn:active,
.qopt:active,
.start-quiz-btn:active,
.review-btn:active,
.wordbook-card-simple:active,
.wb-card:active {
  transform: scale(0.98);
  opacity: 0.9;
  transition: transform 0.1s, opacity 0.1s;
}

/* 对于已经有背景色的按钮，可以变深 */
.capsule:active {
  background: var(--rd);
  color: #fff;
}
@media (max-width: 600px) {
    /* ===== 胶囊按钮缩小并隐藏倒三角 ===== */
  .capsule {
    padding: 6px 12px;
    font-size: 0.8rem;
  }
  .capsule::after {
    display: none;
  }

  /* ===== 筛选选项区域 ===== */
  .filter-row {
    flex-wrap: wrap;
  }
  .filter-capsules {
    width: 100%;
    overflow-x: visible;
    flex-wrap: wrap;
    margin-bottom: 8px;
  }
  .active-filters {
    width: 100%;
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
    margin-top: 8px;
    padding: 4px 0;
     display: none;
  }

  /* ===== 右上角按钮组缩小 ===== */
  .fav-container {
    height: 30px;
  }
  .fav-btn,
  .fav-dropdown-btn,
  .detail-btn,
  .mastery-btn {
    width: 26px;
    height: 26px;
    min-width: 26px;
    min-height: 26px;
  }
  .fav-btn {
    font-size: 1.0rem;
  }
  .fav-dropdown-btn {
    font-size: 0.8rem;
  }
  .detail-btn,
  .mastery-btn {
    font-size: 1.0rem;
  }

  /* ===== 单词列表卡片网格布局（圆点独立列）===== */
  .wb-card {
    display: grid;
    grid-template-columns: auto 1fr auto;
    gap: 12px;
    align-items: start;
    padding: 12px;
    background: var(--sur);
    border-radius: var(--radius-card);
    border: 1px solid var(--bd);
    margin-bottom: 8px;
  }
  .wb-dot {
    padding-top: 2px;
  }
  .wb-info {
    overflow: hidden;
    cursor: pointer;
  }
  .wb-word-row {
    display: flex;
    flex-wrap: wrap;
    align-items: baseline;
    gap: 6px;
    margin-bottom: 4px;
  }
  .wb-word {
    font-family: 'Lora', serif;
    font-size: 1rem;
    font-weight: 700;
  }
  .wb-phonetic {
    font-size: 0.7rem;
    color: var(--mu);
  }
  .wb-meaning {
    font-size: 0.85rem;
    margin-bottom: 6px;
    line-height: 1.3;
  }
  .wb-meta {
    display: flex;
    gap: 8px;
    font-size: 0.7rem;
    color: var(--mu);
    align-items: center;
    flex-wrap: wrap;
  }
  .wb-actions {
    display: flex;
    flex-direction: column;
    gap: 4px;
    justify-content: center;
  }
  .wb-btn {
    width: 24px;
    height: 24px;
    font-size: 0.7rem;
    padding: 0;
  }

  /* ===== 其他通用调整 ===== */
  .active-filter {
    padding: 4px 8px;
    font-size: 0.7rem;
    gap: 4px;
  }
  .active-filter .filter-count {
    font-size: 0.6rem;
    padding: 1px 4px;
  }
  .active-filter .remove {
    font-size: 0.9rem;
    margin-left: 2px;
  }

  /* 刷题页胶囊按钮 */
  .qbtn, .conj-btn {
    padding: 4px 8px;
    font-size: 0.6rem;
  }
  .qbtn-count {
    font-size: 0.55rem;
  }
  .qopt {
    padding: 8px 10px;
    font-size: 0.75rem;
  }
  .qc-feedback {
    padding: 10px 16px;
  }
  .next-btn {
    width: 100%;
    margin-top: 8px;
  }
  select.qbtn {
    padding: 4px 20px 4px 8px;
    font-size: 0.6rem;
  }

  /* 变位题输入区域（垂直排列） */
  .conj-input-area {
    flex-direction: column;
    gap: 8px;
  }
  .conj-input-area input,
  .conj-two-inputs {
    width: 100%;
  }
  .conj-input-area button {
    width: 100%;
    padding: 12px 0;
  }
  .conj-two-inputs {
    display: flex;
    gap: 6px;
  }
  .conj-two-inputs input {
    flex: 1;
  }
  .conj-input-area input {
    padding: 10px 12px;
    font-size: 0.9rem;
  }

  /* 复习按钮 */
  .review-btn {
    padding: 12px 16px;
    font-size: 0.9rem;
  }

  /* 单词卡片内边距微调 */
  .wc {
    border-radius: 14px;
  }
  .ct {
    padding: 10px 12px 8px;
  }
  .ir {
    padding: 6px 12px;
  }
  .ex {
    padding: 8px 12px 10px;
  }

  /* 学习中心整体间距 */
  .wordbook-grid-simple {
    gap: 8px;
    margin-bottom: 16px;
  }
  .wordbook-detail-simple {
    padding: 16px;
  }
   /* 重音按钮组：强制一行，允许横向滚动 */
  .accent-bar {
    flex-wrap: nowrap;
    overflow-x: auto;
    -webkit-overflow-scrolling: touch;
    gap: 6px;
    padding-bottom: 4px;
  }
  .accent-bar button {
    flex-shrink: 0;
    width: 34px;
    height: 34px;
    font-size: 0.9rem;
  }
  /* 提交按钮文字不换行 */
  .spell-input-area button{
    white-space: nowrap;
    padding: 0 12px;
    min-width: 56px;
  }
   /* 词本卡片手机端紧凑微调 */
  .wordbook-card-simple {
    gap: 4px 8px;
    padding: 8px;
  }
  .wordbook-card-simple .card-icon {
    width: 28px;
    height: 28px;
    font-size: 1rem;
  }
  .wordbook-card-simple .card-title {
    font-size: 0.8rem;
  }
  .wordbook-card-simple .card-wordcount {
    font-size: 0.7rem;
  }
   .wordbook-card-simple.custom {
    display: flex;
    align-items: center;
    justify-content: center;
    flex-direction: column;
    gap: 6px;
    background: var(--sur);
    border: 1px solid var(--bd);
    border-radius: 20px;
    box-shadow: var(--shadow-card);
    padding: 8px;          /* 与普通卡片内边距一致 */
    min-height: auto;      /* 移除固定最小高度，由内容决定 */
  }
  .wordbook-card-simple.custom .plus-icon {
    font-size: 1.8rem;
    margin: 0;
    color: var(--mu);
  }
  #loading {
  animation: pulse 1.5s infinite;
}
@keyframes pulse {
  0% { opacity: 0.6; }
  50% { opacity: 1; }
  100% { opacity: 0.6; }
}
/* ===== 统计卡片统一布局（确保宽屏水平、窄屏自适应） ===== */

.stats-row {
  display: flex !important;
  flex-wrap: wrap;
  gap: 12px;
  margin-bottom: 24px;
  width: 100%;
}

@media (min-width: 768px) {
  /* 卡片容器 */
  .stats-row {
    flex-wrap: nowrap;
  }
  .stat-card-progress,
  .stat-card-simple {
    padding: 10px 16px;
    gap: 12px;
  }
  /* 环形图容器缩小（宽屏专用） */
  .stat-card-progress .progress-ring-wrapper {
    width: 48px !important;
    height: 48px !important;
  }
  /* 右侧图标容器同步缩小 */
  .stat-card-simple .stat-icon {
    width: 48px !important;
  }
  /* 数值区域字体 */
  .stat-number {
    font-size: 1.6rem;
  }
  .stat-unit {
    font-size: 0.85rem;
    margin-top: 2px;
  }
  /* 右侧竖排汉字 */
  .stat-label {
    font-size: 0.8rem;
    width: 28px;
    letter-spacing: 0.5px;
    writing-mode: vertical-rl;
    text-orientation: upright;
  }
  /* 环形图内部百分比（缩小字体以适应更小的圆） */
  .ring-center {
    font-size: 0.75rem !important;
  }
  .ring-center .percent-symbol {
    font-size: 0.5rem !important;
  }
}

/* 所有卡片基础样式 */
.stat-card-progress,
.stat-card-simple {
  background: var(--sur);
  border-radius: 20px;
  box-shadow: var(--shadow-card);
  padding: 12px 16px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  transition: all 0.2s;
  box-sizing: border-box;
  min-width: 140px;   /* 窄屏换行阈值 */
}

/* 宽屏时内部间距稍大 */
@media (min-width: 768px) {
  .stat-card-progress,
  .stat-card-simple {
    padding: 12px 20px;
    gap: 16px;
  }
}

/* 环形图容器：固定宽高，保证正方形 */
.stat-card-progress .progress-ring-wrapper {
  position: relative;
  width: 56px;
  height: 56px;
  flex-shrink: 0;
}
.stat-card-progress .progress-ring-wrapper svg {
  width: 100%;
  height: 100%;
  display: block;
}
.stat-card-simple .stat-icon {
  flex-shrink: 0;
  width: 50px;
  text-align: center;
  line-height: 1;
}
/* 环形图内部 SVG 填满容器 */
.progress-ring-wrapper svg {
  width: 100%;
  height: 100%;
}
/* 百分比文字绝对居中，并使用 flex 确保内容完全居中 */
.stat-card-progress .ring-center {
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  flex-direction: column;
  font-size: 0.85rem;
  font-weight: bold;
  line-height: 1;
  color: var(--ink);
  white-space: nowrap;
}
.ring-center .percent-symbol {
  font-size: 0.55rem;
}

/* 中间数字+单位 */
.stat-content {
  flex: 1;
  text-align: center;
  display: flex;
  flex-direction: column;
  justify-content: center;
}
.stat-number {
  font-family: 'Lora', serif;
  font-size: 1.3rem;
  font-weight: 700;
  line-height: 1.2;
  color: var(--ink);
}
.stat-unit {
  font-size: 0.7rem;
  color: var(--mu);
  margin-top: 2px;
}

/* 右侧类目文字（垂直书写） */
.stat-label {
  writing-mode: vertical-rl;
  text-orientation: upright;
  font-size: 0.7rem;
  font-weight: 500;
  color: var(--ink2);
  letter-spacing: 0.5px;
  white-space: nowrap;
  flex-shrink: 0;
  text-align: center;
  line-height: 1.3;
  width: 28px;
}

/* 窄屏（<768px）调整 */
@media (max-width: 767px) {
  .stats-row {
    gap: 8px;
    margin-bottom: 20px;
  }
  .stat-card-progress,
  .stat-card-simple {
    min-width: 130px;
    padding: 10px 12px;
    gap: 8px;
  }
  .stat-card-progress .progress-ring-wrapper,
  .stat-card-simple .stat-icon {
    width: 42px;
  }
  .progress-ring-wrapper {
    width: 42px;
    height: 42px;
  }
  .stat-number {
    font-size: 1.1rem;
  }
  .stat-unit {
    font-size: 0.65rem;
  }
  .stat-label {
    font-size: 0.65rem;
    width: 24px;
  }
}

/* 极窄屏（<480px）进一步缩小 */
@media (max-width: 480px) {
  .stats-row {
    gap: 6px;
    margin-bottom: 16px;
  }
  .stat-card-progress,
  .stat-card-simple {
    min-width: 110px;
    padding: 8px 10px;
    gap: 6px;
  }
  .stat-card-progress .progress-ring-wrapper,
  .stat-card-simple .stat-icon {
    width: 36px;
  }
  .progress-ring-wrapper {
    width: 36px;
    height: 36px;
  }
  .stat-number {
    font-size: 0.95rem;
  }
  .stat-unit {
    font-size: 0.6rem;
  }
  .stat-label {
    font-size: 0.6rem;
    width: 22px;
  }
}
}
/* 强制学习中心父容器为块级，宽度自适应，移除宽度限制 */
.learning-center-simple {
  max-width:  760px !important;
  padding: 20px 16px !important;
  margin: 0 auto !important;
  background:  #f9f7f2 !important;
  box-sizing: border-box;
}

/* 统计行：宽屏强制水平，占满宽度 */
.stats-row {
  display: flex;
  flex-wrap: nowrap;      /* 强制不换行 */
  gap: 12px;
  margin-bottom: 24px;
  width: 100%;
}

/* 卡片基础样式：均分剩余宽度，允许收缩 */
.stat-card-progress,
.stat-card-simple {
  flex: 1 1 0;           /* 均分剩余空间，允许收缩到0 */
  min-width: 0;          /* 允许收缩到最小，防止溢出 */
  background: var(--sur);
  border-radius: 20px;
  box-shadow: var(--shadow-card);
  padding: 12px 16px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  transition: all 0.2s;
}
/* 默认（宽屏）样式：稍大 */
.stat-card-progress .progress-ring-wrapper,
.stat-card-simple .stat-icon {
  width: 56px;
}
.progress-ring-wrapper {
  width: 56px;
  height: 56px;
}
.stat-number {
  font-size: 1.5rem;
}
.stat-unit {
  font-size: 0.75rem;
}
.stat-label {
  font-size: 0.75rem;
  width: 30px;
}

/* 中等屏幕（平板横屏，1024px 以下）适当缩小 */
@media (max-width: 1023px) {
  .stat-card-progress .progress-ring-wrapper,
  .stat-card-simple .stat-icon {
    width: 48px;
  }
  .progress-ring-wrapper {
    width: 48px;
    height: 48px;
  }
  .stat-number {
    font-size: 1.3rem;
  }
  .stat-unit {
    font-size: 0.7rem;
  }
  .stat-label {
    font-size: 0.7rem;
    width: 28px;
  }
}

/* 窄屏（手机竖屏，768px 以下）进一步缩小，保证不换行 */
@media (max-width: 767px) {
  .stats-row {
    gap: 8px;
  }
  .stat-card-progress,
  .stat-card-simple {
    padding: 8px 12px;
    gap: 8px;
  }
  .stat-card-progress .progress-ring-wrapper,
  .stat-card-simple .stat-icon {
    width: 40px;
  }
  .progress-ring-wrapper {
    width: 40px;
    height: 40px;
  }
  .stat-number {
    font-size: 1rem;
  }
  .stat-unit {
    font-size: 0.6rem;
  }
  .stat-label {
    font-size: 0.6rem;
    width: 24px;
  }
}

/* 极窄屏（<480px）再微调 */
@media (max-width: 480px) {
  .stat-card-progress,
  .stat-card-simple {
    padding: 6px 10px;
    gap: 6px;
  }
  .stat-card-progress .progress-ring-wrapper,
  .stat-card-simple .stat-icon {
    width: 34px;
  }
  .progress-ring-wrapper {
    width: 34px;
    height: 34px;
  }
  .stat-number {
    font-size: 0.9rem;
  }
  .stat-unit {
    font-size: 0.55rem;
  }
  .stat-label {
    font-size: 0.55rem;
    width: 22px;
  }
}
/* 宽屏（≥768px）优化：数值字体更大，右侧竖排汉字更明显 */
@media (min-width: 768px) {
  .stat-card-progress,
  .stat-card-simple {
    padding: 10px 16px;   /* 原来可能是 16px 20px，减少上下内边距 */
    gap: 12px;            /* 适当缩小内部间距 */
  }
  .stat-number {
    font-size: 1.6rem;    /* 数值字体适当，保持清晰 */
  }
  .stat-unit {
    font-size: 0.85rem;
    margin-top: 2px;
  }
  .stat-label {
    font-size: 0.8rem;
    width: 28px;
    letter-spacing: 0.5px;
  }
  .ring-center {
    font-size: 0.9rem;    /* 百分比数字稍大 */
  }
  .ring-center .percent-symbol {
    font-size: 0.6rem;
  }
  /* 调整卡片内边距，让内容更舒展 */
  .stat-card-progress,
  .stat-card-simple {
    padding: 16px 20px;
    gap: 16px;
  }
}
/* ========== 强制环形图百分数居中且不溢出（最终版） ========== */
/* 确保环形图容器始终是正方形 */
.stat-card-progress .progress-ring-wrapper {
  width: 56px !important;
  height: 56px !important;
  position: relative;
  flex-shrink: 0;
}

/* 让 SVG 填满容器 */
.stat-card-progress .progress-ring-wrapper svg {
  width: 100% !important;
  height: 100% !important;
  display: block;
}

/* 百分数文字：强制单行，绝对居中，字体随容器自适应 */
.stat-card-progress .ring-center {
  position: absolute !important;
  top: 0 !important;
  left: 0 !important;
  right: 0 !important;
  bottom: 0 !important;
  display: flex !important;
  align-items: center !important;
  justify-content: center !important;
  flex-direction: row !important;   /* 关键：让数字和百分号在同一行 */
  gap: 2px;
  font-size: clamp(0.6rem, 3vw, 0.85rem);
  font-weight: bold;
  line-height: 1;
  color: var(--ink);
  white-space: nowrap;
}

/* 百分号稍小一点 */
.stat-card-progress .ring-center .percent-symbol {
  font-size: 0.7em;
}

/* 宽屏下（≥768px）缩小环形图尺寸，并同步缩小百分数文字 */
@media (min-width: 768px) {
  .stat-card-progress .progress-ring-wrapper {
    width: 48px !important;
    height: 48px !important;
  }
  .stat-card-progress .ring-center {
    font-size: 0.65rem;
  }
  .stat-card-progress .ring-center .percent-symbol {
    font-size: 0.65em;
  }
}

/* 手机窄屏下保持原有比例 */
@media (max-width: 767px) {
  .stat-card-progress .progress-ring-wrapper {
    width: 42px !important;
    height: 42px !important;
  }
  .stat-card-progress .ring-center {
    font-size: 0.7rem;
  }
}

/* 极小屏（<480px）再缩小 */
@media (max-width: 480px) {
  .stat-card-progress .progress-ring-wrapper {
    width: 36px !important;
    height: 36px !important;
  }
  .stat-card-progress .ring-center {
    font-size: 0.6rem;
  }
}
/* ========== 仅 iPad 竖屏（768px - 1024px）降低卡片高度（减少上下内边距） ========== */
@media (min-width: 768px) and (max-width: 1024px) {
  /* 减小卡片上下内边距，从而降低卡片高度 */
  .stat-card-progress,
  .stat-card-simple {
    padding-top: 8px !important;
    padding-bottom: 8px !important;
    /* 保持左右内边距不变，也可以略微减小，但以您截图为准 */
    padding-left: 16px !important;
    padding-right: 16px !important;
    gap: 10px;               /* 内部元素垂直间距略微缩小 */
  }

  /* 如果环形图容器高度也需要微调，但不影响内容大小 */
  .stat-card-progress .progress-ring-wrapper {
    width: 48px;
    height: 48px;
  }

  /* 右侧图标容器同步调整（可选） */
  .stat-card-simple .stat-icon {
    width: 48px;
  }

  /* 数值与单位之间间距减小 */
  .stat-unit {
    margin-top: 0;
  }
}
/* ========== 语音提示 Toast ========== */
.speech-toast {
    position: fixed;
    bottom: 30px;
    left: 50%;
    transform: translateX(-50%) translateY(100px);
    z-index: 2000;
    transition: transform 0.3s ease, opacity 0.3s;
    opacity: 0;
    pointer-events: none;
}
.speech-toast.show {
    transform: translateX(-50%) translateY(0);
    opacity: 1;
    pointer-events: auto;
}
.speech-toast-content {
    background: var(--sur);
    color: var(--ink);
    border-radius: var(--radius-pill);
    padding: 12px 20px;
    box-shadow: var(--shadow-dropdown);
    border: 1px solid var(--bd);
    font-size: 0.85rem;
    display: flex;
    align-items: center;
    gap: 12px;
    backdrop-filter: blur(8px);
    background: rgba(255,255,255,0.9);
}
body.dark .speech-toast-content {
    background: rgba(30,30,30,0.9);
}
.speech-toast-btn {
    background: var(--rd);
    color: #fff;
    border: none;
    border-radius: var(--radius-button);
    padding: 4px 12px;
    font-size: 0.75rem;
    cursor: pointer;
    transition: opacity 0.2s;
}
.speech-toast-btn:hover {
    opacity: 0.85;
}
.speech-toast-close {
    background: none;
    border: none;
    font-size: 1rem;
    cursor: pointer;
    color: var(--mu);
    padding: 0 4px;
}
.speech-toast-close:hover {
    color: var(--rd);
}

/* ========== 语音引导横幅 ========== */
.speech-banner {
    margin: 8px 16px 0 16px;
    animation: slideDown 0.3s ease;
}
@keyframes slideDown {
    from { opacity: 0; transform: translateY(-20px); }
    to { opacity: 1; transform: translateY(0); }
}
.speech-banner-content {
    background: var(--ams);
    border-left: 4px solid var(--am);
    border-radius: 8px;
    padding: 10px 16px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 12px;
    font-size: 0.8rem;
    color: var(--ink);
    box-shadow: var(--shadow-card);
}
body.dark .speech-banner-content {
    background: rgba(136,92,16,0.2);
}
.speech-banner-content a {
    color: var(--rd);
    text-decoration: none;
    font-weight: 500;
}
.speech-banner-content a:hover {
    text-decoration: underline;
}
.speech-banner-close {
    background: none;
    border: none;
    font-size: 1rem;
    cursor: pointer;
    color: var(--mu);
    padding: 0 4px;
}
.speech-banner-close:hover {
    color: var(--rd);
}

@media (max-width: 600px) {
    .speech-toast-content {
        max-width: 90%;
        flex-wrap: wrap;
        justify-content: center;
        text-align: center;
    }
    .speech-banner-content {
        flex-wrap: wrap;
        justify-content: center;
        text-align: center;
    }
}
/* ========== 帮助中心标签页样式 ========== */
.help-tab {
    background: none;
    border: none;
    padding: 8px 16px;
    font-size: 0.85rem;
    font-weight: 500;
    color: var(--mu);
    cursor: pointer;
    border-bottom: 2px solid transparent;
    transition: all 0.15s;
}
.help-tab:hover {
    color: var(--rd);
}
.help-tab.active {
    color: var(--rd);
    border-bottom-color: var(--rd);
}
.help-tab-content {
    text-align: left;
    padding: 8px 4px;
}
.help-tab-content p {
    margin-bottom: 12px;
}
.help-tab-content hr {
    margin: 12px 0;
    border-color: var(--bd);
}
.filter-option {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 14px 0;
    border-bottom: 1px solid var(--bd);
    cursor: pointer;
}
.filter-option-left {
    display: flex;
    align-items: center;
    gap: 8px;
}
.filter-badge {
    background: var(--rds);
    color: var(--rd);
    font-size: 0.65rem;
    padding: 2px 6px;
    border-radius: 12px;
}
.filter-option-right {
    display: flex;
    align-items: center;
    gap: 12px;
}
.secondary-entry {
    background: none;
    border: none;
    font-size: 1rem;
    color: var(--mu);
    cursor: pointer;
    padding: 4px 8px;
    border-radius: 4px;
}
.secondary-entry:hover {
    background: var(--bg);
    color: var(--rd);
}
@keyframes fadeInUp {
    from { opacity: 0; transform: translateX(-50%) translateY(20px); }
    to { opacity: 1; transform: translateX(-50%) translateY(0); }
}
/* ========== 可折叠底部筛选条 ========== */
.filter-chip-bar {
    position: fixed;
    bottom: 70px;
    left: 12px;
    right: 12px;
    z-index: 150;
    transition: all 0.2s ease;
}

/* The floating chip manager belongs to vocabulary browsing only. Quiz setup has
   its own range summary and fixed primary action; showing both obscures taps. */
body:not([data-active-page="vocab"]) .filter-chip-bar {
    display: none !important;
}
/* 展开状态样式 */
.filter-chip-bar:not(.collapsed) .filter-chip-expanded {
    background: rgba(255,255,255,0.95);
    backdrop-filter: blur(8px);
    border-radius: 48px;
    box-shadow: 0 2px 8px rgba(0,0,0,0.1);
    padding: 6px 12px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 8px;
    border: 1px solid var(--bd);
}
.filter-chip-bar.collapsed .filter-chip-expanded {
    display: none;
}
.filter-chip-bar:not(.collapsed) .filter-chip-collapsed {
    display: none;
}
.filter-chip-bar.collapsed .filter-chip-collapsed {
    display: flex;
}

/* 展开状态内部组件 */
.filter-chips-container {
    display: flex;
    flex-wrap: nowrap;
    overflow-x: auto;
    gap: 8px;
    flex: 1;
    scrollbar-width: none;
}
.filter-chips-container::-webkit-scrollbar {
    display: none;
}
.filter-chip {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    background: var(--rds);
    border: 1px solid var(--rd);
    border-radius: 30px;
    padding: 4px 10px;
    font-size: 0.7rem;
    color: var(--rd);
    white-space: nowrap;
    flex-shrink: 0;
}
.filter-chip .chip-label {
    max-width: 100px;
    overflow: hidden;
    text-overflow: ellipsis;
}
.filter-chip .chip-remove {
    cursor: pointer;
    font-weight: bold;
    font-size: 1rem;
    line-height: 1;
    opacity: 0.7;
}
.clear-all-chips {
    background: none;
    border: none;
    font-size: 1.2rem;
    cursor: pointer;
    color: var(--mu);
    padding: 4px 8px;
    border-radius: 30px;
    flex-shrink: 0;
}
.clear-all-chips:active {
    background: rgba(0,0,0,0.05);
}
body.dark .clear-all-chips:active {
    background: rgba(255,255,255,0.1);
}

/* 收起状态圆形按钮 */
.filter-chip-collapsed {
    width: 52px;
    height: 52px;
    border-radius: 52px;
    background: var(--rd);
    color: white;
    border: none;
    box-shadow: 0 4px 12px rgba(0,0,0,0.2);
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    transition: transform 0.2s;
    margin-left: auto;
    margin-right: 0;
}
.filter-chip-collapsed:active {
    transform: scale(0.95);
}
.filter-chip-collapsed #collapsedBadge {
    font-size: 0.7rem;
    font-weight: bold;
    background: rgba(255,255,255,0.3);
    border-radius: 20px;
    padding: 0 4px;
    min-width: 18px;
    text-align: center;
    line-height: 1.2;
}
.filter-chip-collapsed .filter-icon {
    font-size: 1.2rem;
}

/* 深色模式 */
body.dark .filter-chip-bar:not(.collapsed) .filter-chip-expanded {
    background: rgba(30,30,30,0.95);
    border-color: var(--bd);
}

/* 手机端位置微调 */
@media (max-width: 600px) {
    .filter-chip-bar {
        bottom: 70px;
        left: 8px;
        right: 8px;
    }
    .filter-chip-collapsed {
        width: 48px;
        height: 48px;
    }
}
@media (min-width: 1024px) {
    .filter-chip-bar {
        bottom: 30px;
        left: auto;
        right: 20px;
        width: auto;
        max-width: 80%;
    }
    .filter-chip-collapsed {
        margin-left: auto;
    }
}
/* 修改密码输入框样式 */
.pwd-input {
    width: 100%;
    padding: 12px;
    border: 1px solid var(--bd);
    border-radius: 8px;
    background: var(--sur);
    color: var(--ink);
    font-size: 0.9rem;
    outline: none;
    transition: border-color 0.2s;
}
.pwd-input:focus {
    border-color: var(--rd);
}
.pwd-input::placeholder {
    color: var(--mu);
}
.pwd-input {
    width: 100%;
    padding: 12px;
    border: 1px solid var(--bd);
    border-radius: 8px;
    background: var(--sur);
    color: var(--ink);
    font-size: 0.9rem;
    outline: none;
}
.pwd-input:focus {
    border-color: var(--rd);
}
/* 答题页面返回按钮 */
.quiz-back-btn {
    background: var(--bg);
    border: 1px solid var(--bd);
    border-radius: 30px;
    padding: 6px 14px;
    font-size: 0.75rem;
    color: var(--mu);
    cursor: pointer;
    transition: all 0.2s;
    margin-left: 10px;
    white-space: nowrap;
}
.quiz-back-btn:hover {
    background: var(--rds);
    border-color: var(--rd);
    color: var(--rd);
}
/* ========== 大屏适配：拉伸宽度 + 放大元素（不增加列数） ========== */

/* 基础样式：所有页面容器 */
.main, .quiz-wrap, .learning-center-simple {
    transition: max-width 0.2s ease;
    margin: 0 auto;
}

/* 平板竖屏 (768px - 1024px) */
@media (min-width: 768px) and (max-width: 1024px) {
    .main, .quiz-wrap, .learning-center-simple {
        max-width: 90%;
        padding-left: 20px;
        padding-right: 20px;
    }
}

/* 桌面显示器 (1024px - 1440px) */
@media (min-width: 1024px) and (max-width: 1440px) {
    .main, .quiz-wrap, .learning-center-simple {
        max-width: 1000px;
    }
    /* 放大字体和间距 */
    .wd {
        font-size: 1.6rem;
    }
    .irv {
        font-size: 0.95rem;
    }
    .ph {
        font-size: 0.85rem;
    }
    .capsule, .qbtn, .fb, .pill, .conj-btn {
        padding: 8px 20px;
        font-size: 0.9rem;
    }
    .qopt {
        padding: 16px 18px;
        font-size: 0.95rem;
    }
    .qc-question {
        font-size: 1.8rem;
    }
    .hero h1 {
        font-size: 1.8rem;
    }
    .wordbook-card-simple {
        padding: 16px;
    }
    .card-title {
        font-size: 1rem;
    }
}

/* 大屏显示器 (1440px - 1920px) */
@media (min-width: 1440px) and (max-width: 1920px) {
    .main, .quiz-wrap, .learning-center-simple {
        max-width: 1200px;
    }
    .wd {
        font-size: 1.8rem;
    }
    .irv {
        font-size: 1.05rem;
    }
    .ph {
        font-size: 0.95rem;
    }
    .capsule, .qbtn, .fb, .pill, .conj-btn {
        padding: 10px 24px;
        font-size: 1rem;
    }
    .qopt {
        padding: 18px 22px;
        font-size: 1rem;
    }
    .qc-question {
        font-size: 2rem;
    }
    .hero h1 {
        font-size: 2rem;
    }
    .hero .sn {
        font-size: 1.5rem;
    }
    .wordbook-card-simple {
        padding: 20px;
    }
    .card-title {
        font-size: 1.1rem;
    }
}

/* 超宽屏 (1920px 以上) */
@media (min-width: 1920px) {
    .main, .quiz-wrap, .learning-center-simple {
        max-width: 1400px;
    }
    .wd {
        font-size: 2rem;
    }
    .irv {
        font-size: 1.1rem;
    }
    .ph {
        font-size: 1rem;
    }
    .capsule, .qbtn, .fb, .pill, .conj-btn {
        padding: 12px 28px;
        font-size: 1.05rem;
    }
    .qopt {
        padding: 20px 24px;
        font-size: 1.05rem;
    }
    .qc-question {
        font-size: 2.2rem;
    }
    .hero h1 {
        font-size: 2.2rem;
    }
    .wordbook-card-simple {
        padding: 24px;
    }
    .card-title {
        font-size: 1.2rem;
    }
}
.pronounce-word {
    cursor: pointer;
    transition: color 0.1s;
}
.pronounce-word:hover {
    color: var(--rd);
    text-decoration: underline;
}
/* 教材进度看板样式 */
.pg-group {
    border: 1px solid var(--bd);
    border-radius: 12px;
    margin-bottom: 12px;
    overflow: hidden;
    background: var(--sur);
}
.pg-group-head {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 12px 16px;
    cursor: pointer;
    background: var(--bg);
    transition: background 0.2s;
}
.pg-group-head:hover {
    background: var(--bd);
}
.pg-group-left {
    display: flex;
    align-items: center;
    gap: 12px;
    flex-wrap: wrap;
}
.pg-group-dot {
    width: 10px;
    height: 10px;
    border-radius: 50%;
    flex-shrink: 0;
}
.pg-group-label {
    font-weight: 600;
    font-size: 0.9rem;
}
.pg-group-sub {
    font-size: 0.7rem;
    color: var(--mu);
}
.pg-group-right {
    display: flex;
    align-items: center;
    gap: 12px;
}
.pg-mini-bar {
    width: 80px;
    height: 6px;
    background: var(--bd);
    border-radius: 3px;
    overflow: hidden;
}
.pg-mini-fill {
    height: 100%;
    border-radius: 3px;
}
.pg-group-pct {
    font-size: 0.75rem;
    font-weight: 500;
    min-width: 40px;
}
.pg-arrow {
    font-size: 0.7rem;
    transition: transform 0.2s;
}
.pg-arrow.open {
    transform: rotate(180deg);
}
.pg-group-body {
    border-top: 1px solid var(--bd);
}
.pwi2 {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 10px 16px;
    border-bottom: 1px solid var(--bd);
}
.pwi2:last-child {
    border-bottom: none;
}
.pwi2-left {
    display: flex;
    align-items: baseline;
    gap: 10px;
    flex-wrap: wrap;
}
.pwi2-word {
    font-family: 'Lora', serif;
    font-weight: 600;
    font-size: 0.85rem;
}
.pwi2-meaning {
    font-size: 0.7rem;
    color: var(--mu);
}
.pwi2-right {
    display: flex;
    align-items: center;
    gap: 8px;
}
.pwi2-acc {
    font-size: 0.7rem;
    font-family: monospace;
    min-width: 40px;
    text-align: right;
}
.pwi2-toggle {
    width: 28px;
    height: 28px;
    border-radius: 50%;
    border: 1px solid var(--bd);
    background: var(--bg);
    cursor: pointer;
    font-size: 0.8rem;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    transition: all 0.15s;
}
.pwi2-toggle:hover {
    background: var(--rds);
    border-color: var(--rd);
}
.refresh-progress-btn {
    background: none;
    border: none;
    font-size: 1.2rem;
    cursor: pointer;
    color: var(--mu);
    padding: 0 8px;
}
.refresh-progress-btn:hover {
    color: var(--rd);
}
.review-btn {
    margin-bottom: 20px;
}
#textbookProgressContainer {
    margin-bottom: 24px;
}
.wordbook-grid-simple {
    margin-bottom: 20px;
}
.wordbook-detail-simple {
    margin-top: 0;
}

/* ===== Stage 4: shared responsive application shell ===== */
.tb {
  min-height: calc(var(--header-height) + env(safe-area-inset-top));
  height: auto;
  padding-top: env(safe-area-inset-top);
}

.logo sub {
  min-width: 4em;
}

body[data-active-page]:not([data-active-page="vocab"]) .hero {
  display: none;
}

.page-tabs {
  position: sticky;
  top: calc(var(--header-height) + env(safe-area-inset-top));
  z-index: 88;
}

.ptab {
  min-height: var(--touch-target);
  transition:
    color var(--duration-fast) var(--ease-standard),
    border-color var(--duration-fast) var(--ease-standard),
    background var(--duration-fast) var(--ease-standard);
}

.page-view {
  min-height: calc(100dvh - var(--header-height));
}

.page-view[aria-hidden="true"] {
  visibility: hidden;
}

.ctrl {
  top: calc(var(--header-height) + env(safe-area-inset-top));
}

.bottom-nav {
  min-height: calc(var(--mobile-nav-height) + env(safe-area-inset-bottom));
  height: auto;
  padding-right: env(safe-area-inset-right);
  padding-bottom: env(safe-area-inset-bottom);
  padding-left: env(safe-area-inset-left);
  background: color-mix(in srgb, var(--color-surface-raised) 88%, transparent);
  border-top-color: color-mix(in srgb, var(--color-border) 82%, transparent);
  box-shadow: 0 -10px 30px rgba(54, 38, 28, 0.08);
}

body.dark .bottom-nav {
  background: color-mix(in srgb, var(--color-surface-raised) 88%, transparent);
  border-top-color: color-mix(in srgb, var(--color-border) 82%, transparent);
}

.nav-item {
  min-height: var(--mobile-nav-height);
  transition:
    color var(--duration-fast) var(--ease-standard),
    background var(--duration-fast) var(--ease-standard);
}

.nav-item.active {
  background: linear-gradient(180deg, transparent, var(--color-primary-soft));
}

@media (max-width: 1023px) {
  body[data-active-page]:not([data-active-page="vocab"]) .tb {
    box-shadow: 0 1px 0 rgba(255, 255, 255, 0.08);
  }

  .main,
  .quiz-wrap,
  .learning-center-simple {
    padding-bottom: calc(var(--mobile-nav-height) + env(safe-area-inset-bottom) + var(--space-6));
  }

  :where(.capsule, .qbtn, .start-quiz-btn, .review-btn, .quiz-back-btn, .next-btn, .qr-btn) {
    min-height: var(--touch-target);
  }
}

@media (min-width: 1024px) {
  .main,
  .quiz-wrap,
  .learning-center-simple {
    width: min(100%, var(--content-max));
  }

  .quiz-wrap {
    max-width: var(--reading-max);
  }
}

@media (prefers-reduced-motion: reduce) {
  html:focus-within {
    scroll-behavior: auto;
  }

  *,
  *::before,
  *::after {
    scroll-behavior: auto !important;
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }
}

/* ===== Stage 4: learning center work surface ===== */
#pv-wordbook {
  background: var(--color-surface-sunken);
}

.learning-center-content,
.learning-center-locked {
  min-height: calc(100dvh - var(--header-height));
}

.learning-center-simple {
  display: grid;
  gap: var(--space-5);
  width: min(100%, var(--learning-center-max)) !important;
  max-width: var(--learning-center-max) !important;
  margin: 0 auto !important;
  padding: clamp(var(--space-4), 4vw, var(--space-7)) !important;
  background: transparent !important;
}

.learning-eyebrow {
  margin: 0 0 var(--space-1);
  color: var(--color-primary);
  font-size: 0.72rem;
  font-weight: 800;
  letter-spacing: 0.12em;
  line-height: 1.4;
  text-transform: uppercase;
}

.learning-overview {
  display: grid;
  gap: var(--space-5);
  padding: clamp(var(--space-5), 5vw, var(--space-8));
  color: var(--color-text);
  background: linear-gradient(145deg, var(--color-primary-soft), var(--color-surface-raised) 62%);
  border: 1px solid color-mix(in srgb, var(--color-primary) 22%, var(--color-border));
  border-radius: var(--radius-xl);
  box-shadow: var(--elevation-2);
}

.learning-overview-top {
  display: grid;
  gap: var(--space-5);
}

.learning-overview-copy h1,
.learning-auth-gate h1 {
  margin: 0;
  font-family: 'Lora', serif;
  font-size: clamp(1.55rem, 6vw, 2.35rem);
  line-height: 1.2;
  letter-spacing: -0.025em;
}

.learning-overview-copy > p:last-child,
.learning-auth-gate > p:last-of-type {
  max-width: 40rem;
  margin: var(--space-2) 0 0;
  color: var(--color-text-muted);
  font-size: 0.92rem;
  line-height: 1.65;
}

.learning-goal-panel {
  display: flex;
  align-items: center;
  gap: var(--space-4);
  min-width: min(100%, 15.5rem);
  padding: var(--space-4);
  background: color-mix(in srgb, var(--color-surface-raised) 78%, transparent);
  border: 1px solid color-mix(in srgb, var(--color-primary) 16%, var(--color-border));
  border-radius: var(--radius-lg);
}

.learning-goal-panel .progress-ring-wrapper {
  position: relative;
  width: 4.5rem !important;
  height: 4.5rem !important;
  flex: 0 0 4.5rem;
}

.learning-goal-panel .progress-ring-wrapper svg {
  display: block;
  width: 100%;
  height: 100%;
}

.learning-goal-panel .ring-bg {
  stroke: color-mix(in srgb, var(--color-primary) 14%, var(--color-border));
}

.learning-goal-panel .ring-fill {
  stroke: var(--color-primary);
  transition: stroke-dashoffset var(--duration-slow) var(--ease-standard);
}

.learning-goal-panel .ring-center {
  position: absolute;
  inset: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 0.1rem;
  color: var(--color-text);
  font-size: 0.9rem;
  font-weight: 800;
  line-height: 1;
}

.learning-goal-panel .percent-symbol {
  font-size: 0.65em;
}

.learning-goal-copy {
  display: grid;
  gap: 0.12rem;
  min-width: 0;
}

.learning-goal-copy > span,
.learning-goal-copy small {
  color: var(--color-text-muted);
  font-size: 0.75rem;
}

.learning-goal-copy strong {
  color: var(--color-text);
  font-family: 'Lora', serif;
  font-size: 1.4rem;
  line-height: 1.25;
}

.learning-goal-copy strong span:last-child {
  margin-left: 0.2rem;
  color: var(--color-text-muted);
  font-family: inherit;
  font-size: 0.72rem;
  font-weight: 600;
}

.learning-primary-action {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-4);
  width: 100%;
  min-height: 4rem;
  padding: var(--space-3) var(--space-4);
  color: var(--color-primary-contrast);
  text-align: left;
  background: var(--color-primary);
  border: 1px solid var(--color-primary);
  border-radius: var(--radius-lg);
  box-shadow: 0 10px 24px color-mix(in srgb, var(--color-primary) 24%, transparent);
  cursor: pointer;
  transition:
    transform var(--duration-fast) var(--ease-standard),
    background var(--duration-fast) var(--ease-standard),
    box-shadow var(--duration-fast) var(--ease-standard);
}

.learning-primary-action > span:first-child {
  display: grid;
  gap: 0.1rem;
}

.learning-primary-action strong {
  font-size: 0.98rem;
}

.learning-primary-action small {
  color: color-mix(in srgb, var(--color-primary-contrast) 80%, transparent);
  font-size: 0.72rem;
}

.learning-action-arrow {
  display: inline-grid;
  width: 2rem;
  height: 2rem;
  flex: 0 0 2rem;
  place-items: center;
  background: color-mix(in srgb, var(--color-primary-contrast) 16%, transparent);
  border-radius: 50%;
  font-size: 1.1rem;
}

.learning-metrics {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: var(--space-2);
}

.learning-metric {
  display: flex;
  align-items: center;
  gap: var(--space-2);
  min-width: 0;
  padding: var(--space-3);
  background: var(--color-surface-raised);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
}

.learning-metric-icon {
  display: inline-grid;
  width: 2rem;
  height: 2rem;
  flex: 0 0 2rem;
  place-items: center;
  background: var(--color-surface-subtle);
  border-radius: var(--radius-sm);
}

.learning-metric > div {
  display: grid;
  gap: 0.05rem;
  min-width: 0;
}

.learning-metric strong {
  color: var(--color-text);
  font-family: 'Lora', serif;
  font-size: 0.94rem;
  line-height: 1.2;
  white-space: nowrap;
}

.learning-metric div > span {
  overflow: hidden;
  color: var(--color-text-muted);
  font-size: 0.66rem;
  line-height: 1.4;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.learning-section {
  min-width: 0;
  padding: clamp(var(--space-4), 4vw, var(--space-6));
  background: var(--color-surface-raised);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  box-shadow: var(--elevation-1);
}

.learning-section-heading,
.detail-header {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: var(--space-4);
  margin: 0 0 var(--space-4);
  padding: 0 0 var(--space-4);
  border-bottom: 1px solid var(--color-border);
}

.learning-section-heading h2,
.detail-title {
  margin: 0;
  color: var(--color-text);
  font-family: 'Lora', serif;
  font-size: clamp(1.15rem, 4vw, 1.4rem);
  line-height: 1.3;
}

.learning-section-heading > div > p:last-child {
  max-width: 34rem;
  margin: var(--space-1) 0 0;
  color: var(--color-text-muted);
  font-size: 0.8rem;
  line-height: 1.55;
}

.learning-report-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: var(--space-3);
}

.learning-report-grid[hidden],
.learning-recommendations[hidden] {
  display: none;
}

.learning-report-grid article {
  display: grid;
  min-width: 0;
  padding: var(--space-3);
  gap: 0.2rem;
  background: var(--color-surface-subtle);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
}

.learning-report-grid span,
.learning-report-grid small,
.learning-recommendations-heading span,
.learning-recommendation-item small {
  color: var(--color-text-muted);
  font-size: 0.7rem;
  line-height: 1.45;
}

.learning-report-grid strong {
  color: var(--color-text);
  font-family: 'Lora', serif;
  font-size: 1.25rem;
}

.learning-recommendations {
  margin-top: var(--space-5);
  padding-top: var(--space-4);
  border-top: 1px solid var(--color-border);
}

.learning-recommendations-heading {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: var(--space-3);
  margin-bottom: var(--space-3);
}

.learning-recommendations-heading h3 {
  margin: 0;
  color: var(--color-text);
  font-size: 0.9rem;
}

.learning-recommendation-list {
  display: grid;
  gap: var(--space-2);
}

.learning-recommendation-item {
  display: flex;
  min-width: 0;
  min-height: var(--touch-target);
  padding: var(--space-3);
  align-items: center;
  justify-content: space-between;
  gap: var(--space-3);
  background: var(--color-surface-subtle);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
}

button.learning-recommendation-item {
  width: 100%;
  color: var(--color-text);
  font: inherit;
  text-align: left;
  cursor: pointer;
}

.learning-recommendation-item > div {
  display: grid;
  min-width: 0;
  gap: 0.1rem;
}

.learning-recommendation-item strong,
.learning-recommendation-item span {
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.learning-recommendation-item > strong {
  flex: 0 0 auto;
  color: var(--color-primary);
  font-size: 0.78rem;
}

.learning-secondary-action,
.refresh-progress-btn {
  min-height: var(--touch-target);
  padding: 0 var(--space-3);
  color: var(--color-primary);
  font-weight: 700;
  white-space: nowrap;
  background: var(--color-primary-soft);
  border: 1px solid color-mix(in srgb, var(--color-primary) 24%, var(--color-border));
  border-radius: var(--radius-md);
  cursor: pointer;
}

.wordbook-grid-simple {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: var(--space-3);
  margin: 0;
}

.wordbook-card-shell {
  position: relative;
  min-width: 0;
}

.wordbook-card-shell > .wordbook-card-simple {
  height: 100%;
}

.wordbook-menu-toggle {
  position: absolute;
  z-index: 2;
  top: 0.55rem;
  right: 0.55rem;
  width: 2rem;
  height: 2rem;
  padding: 0;
  color: var(--color-text-muted);
  background: color-mix(in srgb, var(--color-surface-raised) 92%, transparent);
  border: 1px solid var(--color-border);
  border-radius: 999px;
  cursor: pointer;
}

.wordbook-card-menu {
  position: absolute;
  z-index: 5;
  top: 2.8rem;
  right: 0.55rem;
  min-width: 7.5rem;
  padding: 0.35rem;
  background: var(--color-surface-raised);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
  box-shadow: var(--elevation-2);
}

.wordbook-card-menu[hidden] {
  display: none;
}

.wordbook-card-menu button {
  display: block;
  width: 100%;
  padding: 0.65rem 0.75rem;
  color: var(--color-text);
  text-align: left;
  background: transparent;
  border: 0;
  border-radius: 0.45rem;
  cursor: pointer;
}

.wordbook-card-menu button:hover {
  background: var(--color-primary-soft);
}

.wordbook-card-menu button.is-danger {
  color: var(--color-danger, #a83225);
}

.vocabulary-resume {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-4);
  max-width: 1280px;
  margin: var(--space-3) auto 0;
  padding: var(--space-3) var(--space-4);
  background: var(--color-primary-soft);
  border: 1px solid color-mix(in srgb, var(--color-primary) 30%, var(--color-border));
  border-radius: var(--radius-md);
}

.vocabulary-resume[hidden] {
  display: none;
}

.vocabulary-resume-copy {
  display: grid;
  gap: 0.2rem;
}

.vocabulary-resume-kicker {
  color: var(--color-primary);
  font-size: 0.72rem;
  font-weight: 800;
  letter-spacing: 0.08em;
}

.vocabulary-resume-copy strong {
  color: var(--color-text);
}

.vocabulary-resume-copy > span:last-child {
  color: var(--color-text-muted);
  font-size: 0.85rem;
}

.vocabulary-resume-actions {
  display: flex;
  flex-wrap: wrap;
  justify-content: flex-end;
  gap: var(--space-2);
}

.vocabulary-resume-actions button {
  min-height: var(--touch-target);
  padding: 0 var(--space-3);
  color: var(--color-text);
  background: var(--color-surface-raised);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
  cursor: pointer;
}

.vocabulary-resume-actions .vocabulary-resume-primary {
  color: var(--color-primary-contrast);
  background: var(--color-primary);
  border-color: var(--color-primary);
}

.wc.vocabulary-resume-target {
  outline: 3px solid color-mix(in srgb, var(--color-primary) 55%, transparent);
  outline-offset: 3px;
}

@media (max-width: 720px) {
  .vocabulary-resume {
    align-items: stretch;
    flex-direction: column;
    margin-inline: var(--space-2);
  }

  .vocabulary-resume-actions {
    display: grid;
    grid-template-columns: 1fr 1fr;
  }

  .vocabulary-resume-actions .vocabulary-resume-primary {
    grid-column: 1 / -1;
  }
}

button.wordbook-card-simple {
  position: relative;
  display: grid;
  grid-template-columns: auto minmax(0, 1fr);
  grid-template-rows: auto auto auto;
  gap: var(--space-1) var(--space-3);
  width: 100%;
  min-height: 5.5rem;
  padding: var(--space-3);
  color: var(--color-text);
  text-align: left;
  background: var(--color-surface-raised);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  box-shadow: none;
  cursor: pointer;
  transition:
    border-color var(--duration-fast) var(--ease-standard),
    background var(--duration-fast) var(--ease-standard),
    transform var(--duration-fast) var(--ease-standard);
}

button.wordbook-card-simple.is-active {
  background: var(--color-primary-soft);
  border-color: var(--color-primary);
  box-shadow: inset 0 0 0 1px var(--color-primary);
}

button.wordbook-card-simple .card-icon {
  grid-row: 1;
  grid-column: 1;
  width: 2.5rem;
  height: 2.5rem;
  margin: 0;
  align-self: center;
  border-radius: var(--radius-sm);
}

button.wordbook-card-simple .card-title {
  grid-row: 2;
  grid-column: 1 / -1;
  align-self: end;
  margin: 0;
  color: var(--color-text);
  font-family: inherit;
  font-size: 0.88rem;
  font-weight: 800;
}

button.wordbook-card-simple .card-wordcount {
  grid-row: 3;
  grid-column: 1 / -1;
  align-self: start;
  color: var(--color-text-muted);
  font-size: 0.72rem;
  text-align: left;
}

button.wordbook-card-simple .card-badge {
  position: static;
  grid-row: 1;
  grid-column: 2;
  min-width: 1.75rem;
  align-self: center;
  justify-self: end;
  padding: 0.15rem 0.4rem;
  color: var(--color-primary-contrast);
  background: var(--color-primary);
  border-radius: 999px;
  font-size: 0.68rem;
  text-align: center;
}

.learning-section.wordbook-detail-simple {
  margin: 0;
  background: var(--color-surface-raised);
  border-radius: var(--radius-lg);
  box-shadow: var(--elevation-1);
}

.detail-count {
  display: inline-flex;
  min-height: 2rem;
  align-items: center;
  padding: 0 var(--space-2);
  color: var(--color-text-muted);
  background: var(--color-surface-subtle);
  border-radius: 999px;
  font-size: 0.75rem;
  white-space: nowrap;
}

#pv-wordbook .wb-list {
  display: grid;
  gap: var(--space-2);
}

#pv-wordbook .wb-card {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr);
  gap: var(--space-2) var(--space-3);
  align-items: center;
  margin: 0;
  padding: var(--space-3);
  background: var(--color-surface-subtle);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  box-shadow: none;
}

#pv-wordbook .wb-dot {
  grid-row: 1;
  grid-column: 1;
  align-self: start;
  padding-top: 0.65rem;
}

#pv-wordbook .wb-info {
  display: block;
  grid-row: 1;
  grid-column: 2;
  width: 100%;
  min-width: 0;
  min-height: var(--touch-target);
  padding: 0;
  color: var(--color-text);
  text-align: left;
  background: transparent;
  border: 0;
  cursor: pointer;
}

#pv-wordbook .wb-actions {
  display: flex;
  grid-row: 2;
  grid-column: 2;
  flex-direction: row;
  gap: var(--space-2);
  justify-content: flex-start;
}

#pv-wordbook .wb-btn {
  width: var(--touch-target);
  height: var(--touch-target);
  min-width: var(--touch-target);
  min-height: var(--touch-target);
  padding: 0;
  color: var(--color-text-muted);
  background: var(--color-surface-raised);
  border: 1px solid var(--color-border);
}

.empty-guide {
  display: grid;
  justify-items: center;
  gap: var(--space-2);
  padding: var(--space-6) var(--space-3);
  color: var(--color-text-muted);
  text-align: center;
}

.empty-guide-compact {
  padding-top: var(--space-3);
  padding-bottom: var(--space-4);
}

.empty-guide-icon {
  font-size: 1.7rem;
}

.empty-guide h3,
.empty-guide p {
  margin: 0;
}

.empty-guide h3 {
  color: var(--color-text);
  font-family: 'Lora', serif;
  font-size: 1.05rem;
}

.recommend-list {
  border-top: 1px solid var(--color-border);
}

.recommend-word-item {
  gap: var(--space-3);
  padding: var(--space-2) 0;
  border-bottom: 1px solid var(--color-border);
}

.recommend-word-item > div {
  min-width: 0;
}

.recommend-word-item .word {
  min-height: var(--touch-target);
  padding: 0;
  color: var(--color-text);
  text-align: left;
  background: transparent;
  border: 0;
}

.recommend-word-item .add-btn {
  min-height: var(--touch-target);
  padding: 0 var(--space-3);
  color: var(--color-primary);
  font-weight: 700;
  background: var(--color-primary-soft);
  border: 1px solid color-mix(in srgb, var(--color-primary) 22%, var(--color-border));
  border-radius: var(--radius-md);
}

.learning-textbook-section {
  overflow: hidden;
  padding: 0;
}

.textbook-progress-disclosure > summary {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-4);
  min-height: 5.25rem;
  padding: var(--space-4) clamp(var(--space-4), 4vw, var(--space-6));
  cursor: pointer;
  list-style: none;
}

.textbook-progress-disclosure > summary::-webkit-details-marker {
  display: none;
}

.textbook-progress-disclosure summary > span:first-child {
  display: grid;
  gap: 0.12rem;
}

.textbook-progress-disclosure summary strong {
  color: var(--color-text);
  font-family: 'Lora', serif;
  font-size: 1.12rem;
}

.textbook-progress-disclosure summary small {
  color: var(--color-text-muted);
  font-size: 0.75rem;
  line-height: 1.45;
}

.learning-disclosure-chevron {
  display: inline-grid;
  width: var(--touch-target);
  height: var(--touch-target);
  flex: 0 0 var(--touch-target);
  place-items: center;
  color: var(--color-text-muted);
  background: var(--color-surface-subtle);
  border-radius: 50%;
  transition: transform var(--duration-fast) var(--ease-standard);
}

.textbook-progress-disclosure[open] .learning-disclosure-chevron {
  transform: rotate(180deg);
}

.textbook-progress-toolbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-4);
  padding: var(--space-3) clamp(var(--space-4), 4vw, var(--space-6));
  background: var(--color-surface-subtle);
  border-top: 1px solid var(--color-border);
  border-bottom: 1px solid var(--color-border);
}

.textbook-progress-toolbar p {
  margin: 0;
  color: var(--color-text-muted);
  font-size: 0.75rem;
  line-height: 1.5;
}

#textbookProgressContainer {
  margin: 0;
}

.learning-inline-status {
  margin: 0;
  padding: var(--space-5);
  color: var(--color-text-muted);
  text-align: center;
}

#pv-wordbook .pg-groups {
  display: grid;
  gap: 0;
  margin: 0;
}

#pv-wordbook .pg-group {
  overflow: hidden;
  margin: 0;
  background: var(--color-surface-raised);
  border: 0;
  border-bottom: 1px solid var(--color-border);
  border-radius: 0;
}

#pv-wordbook .pg-group:last-child {
  border-bottom: 0;
}

#pv-wordbook .pg-group-head {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-3);
  width: 100%;
  min-height: 4rem;
  padding: var(--space-3) clamp(var(--space-4), 4vw, var(--space-6));
  color: var(--color-text);
  text-align: left;
  background: var(--color-surface-raised);
  border: 0;
  border-radius: 0;
  cursor: pointer;
}

#pv-wordbook .pg-group-left {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr);
  gap: 0 var(--space-2);
  min-width: 0;
}

#pv-wordbook .pg-group-dot {
  grid-row: 1 / span 2;
  align-self: center;
}

#pv-wordbook .pg-group-label {
  grid-row: 1;
  grid-column: 2;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

#pv-wordbook .pg-group-sub {
  grid-row: 2;
  grid-column: 2;
  overflow: hidden;
  font-size: 0.67rem;
  text-overflow: ellipsis;
  white-space: nowrap;
}

#pv-wordbook .pg-group-right {
  gap: var(--space-2);
}

#pv-wordbook .pg-mini-bar {
  width: 3.5rem;
}

#pv-wordbook .pg-group-body {
  background: var(--color-surface-subtle);
  border-top: 1px solid var(--color-border);
}

#pv-wordbook .pg-group-body[hidden] {
  display: none;
}

#pv-wordbook .pg-group-body:not([hidden]) {
  display: block;
}

#pv-wordbook .pwi2 {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: var(--space-2);
  padding: var(--space-3) clamp(var(--space-4), 4vw, var(--space-6));
  border-bottom: 1px solid var(--color-border);
}

#pv-wordbook .pwi2-left {
  gap: var(--space-2);
}

#pv-wordbook .pwi2-right {
  justify-content: flex-end;
  gap: var(--space-2);
}

#pv-wordbook .pwi2-toggle,
#pv-wordbook .pwi2-toggle.review-btn {
  width: var(--touch-target);
  height: var(--touch-target);
  min-width: var(--touch-target);
  min-height: var(--touch-target);
  margin: 0;
  padding: 0;
  color: var(--color-text-muted);
  background: var(--color-surface-raised);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
  box-shadow: none;
}

.learning-auth-gate {
  display: grid;
  justify-items: center;
  max-width: 36rem;
  margin: clamp(var(--space-6), 10vh, 6rem) auto 0;
  padding: clamp(var(--space-6), 8vw, var(--space-9));
  color: var(--color-text);
  text-align: center;
  background: var(--color-surface-raised);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-xl);
  box-shadow: var(--elevation-2);
}

.learning-auth-icon {
  display: inline-grid;
  width: 3.5rem;
  height: 3.5rem;
  margin-bottom: var(--space-3);
  place-items: center;
  background: var(--color-primary-soft);
  border-radius: 50%;
  font-size: 1.5rem;
}

.learning-auth-action {
  width: auto;
  min-width: 9rem;
  min-height: var(--touch-target);
  margin-top: var(--space-5);
  justify-content: center;
  text-align: center;
}

@media (hover: hover) {
  .learning-primary-action:hover {
    background: color-mix(in srgb, var(--color-primary) 88%, #000);
    box-shadow: 0 14px 28px color-mix(in srgb, var(--color-primary) 30%, transparent);
    transform: translateY(-1px);
  }

  button.wordbook-card-simple:hover,
  #pv-wordbook .pg-group-head:hover {
    background: var(--color-primary-soft);
    border-color: color-mix(in srgb, var(--color-primary) 42%, var(--color-border));
  }
}

@media (max-width: 420px) {
  .learning-metric {
    flex-direction: column;
    align-items: flex-start;
  }

  .learning-section-heading {
    align-items: stretch;
    flex-direction: column;
  }

  .learning-secondary-action {
    width: 100%;
  }

  .textbook-progress-toolbar {
    align-items: stretch;
    flex-direction: column;
  }

  #pv-wordbook .pg-mini-bar,
  #pv-wordbook .pg-group-pct {
    display: none;
  }
}

@media (min-width: 640px) {
  .learning-overview-top {
    grid-template-columns: minmax(0, 1fr) auto;
    align-items: center;
  }

  .learning-metrics {
    gap: var(--space-3);
  }

  .wordbook-grid-simple {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }

  button.wordbook-card-simple {
    grid-template-columns: auto minmax(0, 1fr) auto;
    grid-template-rows: auto auto;
  }

  button.wordbook-card-simple .card-icon {
    grid-row: 1 / span 2;
    grid-column: 1;
  }

  button.wordbook-card-simple .card-title {
    grid-row: 1;
    grid-column: 2;
  }

  button.wordbook-card-simple .card-wordcount {
    grid-row: 2;
    grid-column: 2;
  }

  button.wordbook-card-simple .card-badge {
    grid-row: 1 / span 2;
    grid-column: 3;
  }

  #pv-wordbook .wb-card {
    grid-template-columns: auto minmax(0, 1fr) auto;
  }

  #pv-wordbook .wb-info {
    grid-column: 2;
  }

  #pv-wordbook .wb-actions {
    grid-row: 1;
    grid-column: 3;
  }

  #pv-wordbook .pwi2 {
    grid-template-columns: minmax(0, 1fr) auto;
    align-items: center;
  }
}

/* ===== Stage 4: mobile-first quiz setup ===== */
#pv-quiz {
  background: var(--color-surface-sunken);
}

.quiz-wrap {
  width: min(100%, 900px);
  max-width: 900px;
  padding: clamp(var(--space-4), 4vw, var(--space-7));
  padding-bottom: calc(var(--mobile-nav-height) + env(safe-area-inset-bottom) + 8rem);
}

.quiz-settings.quiz-setup {
  display: grid;
  gap: var(--space-4);
  margin: 0;
  padding: 0;
  background: transparent;
  border: 0;
  border-radius: 0;
}

.quiz-setup-header {
  padding: clamp(var(--space-5), 5vw, var(--space-7));
  background: linear-gradient(145deg, var(--color-primary-soft), var(--color-surface-raised) 68%);
  border: 1px solid color-mix(in srgb, var(--color-primary) 20%, var(--color-border));
  border-radius: var(--radius-xl);
  box-shadow: var(--elevation-1);
}

.quiz-eyebrow {
  margin: 0 0 var(--space-1);
  color: var(--color-primary);
  font-size: 0.72rem;
  font-weight: 800;
  letter-spacing: 0.12em;
  line-height: 1.4;
  text-transform: uppercase;
}

.quiz-setup-header h1,
.quiz-auth-gate h1 {
  margin: 0;
  color: var(--color-text);
  font-family: 'Lora', serif;
  font-size: clamp(1.55rem, 6vw, 2.2rem);
  line-height: 1.2;
  letter-spacing: -0.025em;
}

.quiz-setup-header > p:last-child,
.quiz-auth-gate > p:last-of-type {
  max-width: 42rem;
  margin: var(--space-2) 0 0;
  color: var(--color-text-muted);
  font-size: 0.86rem;
  line-height: 1.65;
}

.quiz-setup .qs-section {
  margin: 0;
  padding: clamp(var(--space-4), 4vw, var(--space-5));
  background: var(--color-surface-raised);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
}

.quiz-setup .qs-section:last-of-type {
  margin-bottom: 0;
  border-bottom: 1px solid var(--color-border);
}

.qs-section-heading {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-3);
  margin-bottom: var(--space-3);
}

.quiz-setup .qs-sec-label {
  margin: 0 0 var(--space-3);
  color: var(--color-text);
  font-size: 0.86rem;
  font-weight: 800;
  letter-spacing: 0;
  line-height: 1.4;
}

.qs-section-heading .qs-sec-label {
  margin: 0;
}

.qs-section-heading > span {
  color: var(--color-text-muted);
  font-size: 0.68rem;
}

.quiz-type-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: var(--space-2);
}

.quiz-type-card {
  display: grid;
  gap: var(--space-1);
  min-height: 4.75rem;
  padding: var(--space-3) var(--space-4);
  color: var(--color-text);
  text-align: left;
  background: var(--color-surface-subtle);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  cursor: pointer;
  transition:
    background var(--duration-fast) var(--ease-standard),
    border-color var(--duration-fast) var(--ease-standard),
    transform var(--duration-fast) var(--ease-standard);
}

.quiz-type-card strong {
  font-size: 0.9rem;
}

.quiz-type-card small,
.quiz-scope-card small {
  color: var(--color-text-muted);
  font-size: 0.69rem;
  line-height: 1.45;
}

.quiz-type-card.on,
.quiz-scope-card.on {
  background: var(--color-primary-soft);
  border-color: var(--color-primary);
  box-shadow: inset 0 0 0 1px var(--color-primary);
}

.quiz-direction {
  display: grid;
  gap: var(--space-2);
  margin-top: var(--space-4);
  padding-top: var(--space-4);
  border-top: 1px solid var(--color-border);
}

.quiz-direction .qs-sec-label {
  margin: 0;
}

.quiz-segmented-control {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: var(--space-1);
  padding: var(--space-1);
  background: var(--color-surface-subtle);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
}

.quiz-segmented-control button {
  min-height: var(--touch-target);
  padding: 0 var(--space-2);
  color: var(--color-text-muted);
  background: transparent;
  border: 0;
  border-radius: var(--radius-sm);
  cursor: pointer;
}

.quiz-segmented-control button.on {
  color: var(--color-text);
  font-weight: 800;
  background: var(--color-surface-raised);
  box-shadow: var(--elevation-1);
}

.quiz-scope-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: var(--space-2);
}

.quiz-scope-card {
  display: flex;
  align-items: flex-start;
  gap: var(--space-2);
  min-width: 0;
  min-height: 5.25rem;
  padding: var(--space-3);
  color: var(--color-text);
  text-align: left;
  background: var(--color-surface-subtle);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  cursor: pointer;
}

.quiz-scope-icon {
  flex: 0 0 auto;
  font-size: 1rem;
  line-height: 1.35;
}

.quiz-scope-card > span:last-child {
  display: grid;
  gap: 0.12rem;
  min-width: 0;
}

.quiz-scope-card strong {
  font-size: 0.79rem;
  line-height: 1.35;
}

.quiz-scope-empty-hint {
  margin: var(--space-2) 0 0;
  padding: var(--space-2) var(--space-3);
  color: var(--color-text-muted);
  font-size: 0.7rem;
  line-height: 1.55;
  background: var(--color-surface-subtle);
  border-radius: var(--radius-sm);
}

.quiz-preferences {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: var(--space-2);
}

.quiz-toggle-card {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-4);
  min-height: 4.25rem;
  padding: var(--space-3) var(--space-4);
  background: var(--color-surface-raised);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  cursor: pointer;
}

.quiz-toggle-card > span {
  display: grid;
  gap: 0.12rem;
}

.quiz-toggle-card strong {
  color: var(--color-text);
  font-size: 0.82rem;
}

.quiz-toggle-card small {
  color: var(--color-text-muted);
  font-size: 0.68rem;
}

.quiz-toggle-card input {
  position: relative;
  width: 2.75rem;
  height: 1.6rem;
  flex: 0 0 2.75rem;
  appearance: none;
  background: var(--color-border);
  border: 1px solid var(--color-border);
  border-radius: 999px;
  cursor: pointer;
  transition: background var(--duration-fast) var(--ease-standard);
}

.quiz-toggle-card input::before {
  position: absolute;
  top: 0.18rem;
  left: 0.18rem;
  width: 1.1rem;
  height: 1.1rem;
  content: '';
  background: var(--color-surface-raised);
  border-radius: 50%;
  box-shadow: 0 2px 5px rgba(30, 20, 15, 0.18);
  transition: transform var(--duration-fast) var(--ease-standard);
}

.quiz-toggle-card input:checked {
  background: var(--color-primary);
  border-color: var(--color-primary);
}

.quiz-toggle-card input:checked::before {
  transform: translateX(1.15rem);
}

.quiz-advanced-filters,
.quiz-inline-disclosure {
  overflow: hidden;
  background: var(--color-surface-raised);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
}

.quiz-advanced-filters > summary,
.quiz-inline-disclosure > summary {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-4);
  min-height: 4.75rem;
  padding: var(--space-3) var(--space-4);
  cursor: pointer;
  list-style: none;
}

.quiz-advanced-filters > summary::-webkit-details-marker,
.quiz-inline-disclosure > summary::-webkit-details-marker {
  display: none;
}

.quiz-advanced-filters summary > span:first-child,
.quiz-inline-disclosure summary > span:first-child {
  display: grid;
  gap: 0.1rem;
}

.quiz-advanced-filters summary strong,
.quiz-inline-disclosure summary strong {
  color: var(--color-text);
  font-size: 0.84rem;
}

.quiz-advanced-filters summary small,
.quiz-inline-disclosure summary small {
  color: var(--color-text-muted);
  font-size: 0.68rem;
}

.quiz-disclosure-chevron {
  display: inline-grid;
  width: var(--touch-target);
  height: var(--touch-target);
  flex: 0 0 var(--touch-target);
  place-items: center;
  color: var(--color-text-muted);
  background: var(--color-surface-subtle);
  border-radius: 50%;
  transition: transform var(--duration-fast) var(--ease-standard);
}

.quiz-advanced-filters[open] > summary .quiz-disclosure-chevron,
.quiz-inline-disclosure[open] > summary .quiz-disclosure-chevron {
  transform: rotate(180deg);
}

.quiz-advanced-body,
.quiz-inline-disclosure-body {
  display: grid;
  gap: var(--space-3);
  padding: var(--space-3);
  background: var(--color-surface-subtle);
  border-top: 1px solid var(--color-border);
}

.quiz-advanced-body .qs-section,
.quiz-inline-disclosure-body .qs-section {
  box-shadow: none;
}

.quiz-setup .qs-row,
.conj-tenses-grid,
.conj-persons-grid {
  display: flex;
  gap: var(--space-2);
  margin: 0;
  flex-wrap: wrap;
}

.quiz-setup .qbtn,
.quiz-setup .conj-btn {
  min-height: var(--touch-target);
  padding: 0 var(--space-3);
  color: var(--color-text-muted);
  font: inherit;
  font-size: 0.75rem;
  background: var(--color-surface-subtle);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
}

.quiz-setup .qbtn.on,
.quiz-setup .conj-btn.on {
  color: var(--color-primary-contrast);
  font-weight: 800;
  background: var(--color-primary);
  border-color: var(--color-primary);
}

.qbtn-count {
  margin-left: 0.15rem;
  color: inherit;
  opacity: 0.72;
}

.quiz-empty-option,
#selectedTextbookHint {
  color: var(--color-text-muted);
  font-size: 0.72rem;
}

.quiz-textbook-picker {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  flex-wrap: wrap;
}

.quiz-setup .quiz-textbook-button {
  color: var(--color-primary-contrast);
  font-weight: 800;
  background: var(--color-primary);
  border-color: var(--color-primary);
}

.quiz-start-panel {
  position: fixed;
  right: var(--space-3);
  bottom: calc(var(--mobile-nav-height) + env(safe-area-inset-bottom) + var(--space-2));
  left: var(--space-3);
  z-index: 82;
  display: grid;
  grid-template-columns: auto minmax(0, 1fr);
  gap: var(--space-3);
  width: min(calc(100% - (var(--space-3) * 2)), 860px);
  min-height: 4.5rem;
  margin: 0 auto;
  padding: var(--space-2);
  background: color-mix(in srgb, var(--color-surface-raised) 92%, transparent);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  box-shadow: var(--elevation-2);
  backdrop-filter: blur(14px);
}

.quiz-availability {
  display: flex;
  align-items: baseline;
  align-content: center;
  gap: 0.2rem;
  padding-left: var(--space-2);
  flex-wrap: wrap;
  color: var(--color-text-muted);
  font-size: 0.66rem;
}

.quiz-availability strong {
  color: var(--color-text);
  font-family: 'Lora', serif;
  font-size: 1.15rem;
}

.quiz-availability small {
  width: 100%;
  color: var(--color-primary);
  font-size: 0.64rem;
}

.quiz-start-actions {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr);
  gap: var(--space-2);
}

.quiz-start-panel .qs-clear-btn,
.quiz-start-panel .start-quiz-btn {
  min-height: 3.25rem;
  margin: 0;
  padding: 0 var(--space-3);
  border-radius: var(--radius-md);
}

.quiz-start-panel .qs-clear-btn {
  color: var(--color-text-muted);
  background: var(--color-surface-subtle);
  border: 1px solid var(--color-border);
}

.quiz-start-panel .start-quiz-btn {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-3);
  width: 100%;
  color: var(--color-primary-contrast);
  font: inherit;
  font-size: 0.82rem;
  font-weight: 800;
  letter-spacing: 0;
  background: var(--color-primary);
}

.quiz-auth-gate {
  display: grid;
  justify-items: center;
  max-width: 36rem;
  margin: clamp(var(--space-6), 10vh, 6rem) auto 0;
  padding: clamp(var(--space-6), 8vw, var(--space-9));
  color: var(--color-text);
  text-align: center;
  background: var(--color-surface-raised);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-xl);
  box-shadow: var(--elevation-2);
}

.quiz-auth-icon {
  display: inline-grid;
  width: 3.5rem;
  height: 3.5rem;
  margin-bottom: var(--space-3);
  place-items: center;
  background: var(--color-primary-soft);
  border-radius: 50%;
  font-size: 1.5rem;
}

.quiz-auth-action {
  width: auto;
  min-width: 9rem;
  min-height: var(--touch-target);
  margin-top: var(--space-5);
  padding: 0 var(--space-4);
}

@media (hover: hover) {
  .quiz-type-card:hover,
  .quiz-scope-card:hover {
    border-color: color-mix(in srgb, var(--color-primary) 45%, var(--color-border));
    transform: translateY(-1px);
  }
}

@media (min-width: 600px) {
  .quiz-type-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .quiz-preferences {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

@media (min-width: 760px) {
  .quiz-scope-grid {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }
}

@media (min-width: 1024px) {
  .quiz-type-grid {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

  .quiz-wrap {
    max-width: 900px;
    padding-bottom: var(--space-8);
  }

  .quiz-start-panel {
    position: static;
    width: 100%;
    min-height: 5rem;
    padding: var(--space-3);
    backdrop-filter: none;
  }

  .quiz-start-actions {
    justify-self: end;
    grid-template-columns: auto 12rem;
  }
}

/* ===== Stage 4: mobile-first quiz session and results ===== */
.quiz-card,
.quiz-result {
  width: min(100%, 760px);
  margin: 0 auto;
  overflow: hidden;
  background: var(--color-surface-raised);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-xl);
  box-shadow: var(--elevation-1);
}

.quiz-card {
  animation: slideIn var(--duration-standard) var(--ease-standard);
}

.qc-progress {
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto;
  gap: var(--space-3);
  align-items: center;
  padding: var(--space-3) var(--space-4);
  background: var(--color-surface-subtle);
  border-bottom: 1px solid var(--color-border);
}

.qc-progress-main {
  display: grid;
  gap: var(--space-2);
  min-width: 0;
}

.qc-progress-meta {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-2);
}

.qc-counter,
.qc-score {
  color: var(--color-text-muted);
  font-size: 0.68rem;
  line-height: 1.35;
  white-space: nowrap;
}

.qc-score {
  color: var(--color-success);
  font-weight: 800;
}

.qc-prog-bar {
  height: 0.4rem;
  overflow: hidden;
  background: var(--color-border);
  border-radius: 999px;
}

.qc-prog-fill {
  width: 0;
  height: 100%;
  background: linear-gradient(90deg, var(--color-primary), color-mix(in srgb, var(--color-primary) 70%, var(--color-warning)));
  border-radius: inherit;
  transition: width var(--duration-slow) var(--ease-standard);
}

.quiz-back-btn {
  min-width: var(--touch-target);
  min-height: var(--touch-target);
  padding: 0 var(--space-3);
  color: var(--color-text-muted);
  font: inherit;
  font-size: 0.72rem;
  background: var(--color-surface-raised);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  cursor: pointer;
}

.qc-body {
  display: grid;
  gap: var(--space-3);
  min-height: 22rem;
  padding: clamp(var(--space-5), 7vw, var(--space-8));
  align-content: center;
}

.qc-type-badge {
  margin: 0;
  color: var(--color-primary);
  font-size: 0.68rem;
  font-weight: 800;
  letter-spacing: 0.1em;
  line-height: 1.4;
  text-transform: uppercase;
}

.qc-question-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-3);
}

.qc-question {
  min-width: 0;
  margin: 0;
  color: var(--color-text);
  font-family: 'Lora', serif;
  font-size: clamp(1.8rem, 10vw, 3rem);
  font-weight: 700;
  line-height: 1.15;
  overflow-wrap: anywhere;
}

.qc-question.zh {
  font-family: 'Noto Sans SC', sans-serif;
  font-size: clamp(1.2rem, 6vw, 1.8rem);
  line-height: 1.45;
}

.qc-phonetic,
.qc-conjugation-prompt {
  margin: 0;
  color: var(--color-text-muted);
  font-size: 0.78rem;
  line-height: 1.55;
}

.qc-phonetic {
  font-family: 'JetBrains Mono', monospace;
}

.qc-conjugation-prompt strong {
  color: var(--color-text);
}

.quiz-icon-btn,
.qc-speak,
.qc-hint,
.show-answer-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-2);
  width: auto;
  min-width: var(--touch-target);
  min-height: var(--touch-target);
  padding: 0 var(--space-3);
  color: var(--color-text-muted);
  font: inherit;
  font-size: 0.74rem;
  background: var(--color-surface-subtle);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  cursor: pointer;
}

.qc-question-row .qc-speak {
  flex: 0 0 var(--touch-target);
  width: var(--touch-target);
  padding: 0;
  border-radius: 50%;
}

.quiz-question-actions {
  display: flex;
  gap: var(--space-2);
  align-items: center;
  flex-wrap: wrap;
}

.qc-hint-message {
  margin: 0;
  padding: var(--space-3);
  color: var(--color-info);
  font-size: 0.76rem;
  line-height: 1.5;
  background: var(--color-info-soft);
  border-radius: var(--radius-md);
}

.qc-hint-message[hidden],
.qf-conf[hidden] {
  display: none;
}

.qc-options {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: var(--space-2);
  margin-top: var(--space-2);
}

.qopt {
  position: relative;
  min-height: 3.75rem;
  padding: var(--space-3) 3rem var(--space-3) var(--space-4);
  color: var(--color-text);
  font: inherit;
  font-size: 0.86rem;
  line-height: 1.5;
  text-align: left;
  overflow-wrap: anywhere;
  background: var(--color-surface-subtle);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  cursor: pointer;
  transition:
    background var(--duration-fast) var(--ease-standard),
    border-color var(--duration-fast) var(--ease-standard),
    transform var(--duration-fast) var(--ease-standard);
}

.qopt.correct {
  color: var(--color-success);
  font-weight: 800;
  background: var(--color-success-soft);
  border-color: var(--color-success);
}

.qopt.wrong {
  color: var(--color-danger);
  background: var(--color-danger-soft);
  border-color: var(--color-danger);
}

.qopt:disabled {
  cursor: default;
}

.qopt-mark {
  position: absolute;
  top: 50%;
  right: var(--space-4);
  display: inline-grid;
  width: 1.75rem;
  height: 1.75rem;
  place-items: center;
  font-size: 1rem;
  transform: translateY(-50%);
}

.qc-feedback {
  display: none;
  grid-template-columns: minmax(0, 1fr);
  gap: var(--space-3);
  padding: var(--space-4);
  background: var(--color-surface-subtle);
  border-top: 1px solid var(--color-border);
}

.qc-feedback.show {
  display: grid;
  animation: fadeIn var(--duration-fast) var(--ease-standard);
}

.qf-content {
  display: grid;
  gap: var(--space-2);
  min-width: 0;
}

.qf-result {
  margin: 0;
  font-size: 0.88rem;
  font-weight: 800;
}

.qf-correct {
  color: var(--color-success);
}

.qf-wrong {
  color: var(--color-danger);
}

.qf-answer {
  margin: 0;
  color: var(--color-text-muted);
  font-size: 0.78rem;
  line-height: 1.5;
}

.qf-conf {
  margin-top: var(--space-1);
  padding: var(--space-3);
  color: var(--color-warning);
  font-size: 0.72rem;
  line-height: 1.55;
  background: var(--color-warning-soft);
  border-radius: var(--radius-md);
}

.next-btn {
  width: 100%;
  min-height: 3.25rem;
  padding: 0 var(--space-4);
  color: var(--color-primary-contrast);
  font: inherit;
  font-size: 0.82rem;
  font-weight: 800;
  background: var(--color-primary);
  border: 0;
  border-radius: var(--radius-md);
  cursor: pointer;
}

.spell-input-area,
.conj-input-area {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: var(--space-2);
  margin: var(--space-2) 0 0;
}

.spell-input-area input,
.conj-input-area input {
  width: 100%;
  min-width: 0;
  min-height: 3.25rem;
  padding: 0 var(--space-3);
  color: var(--color-text);
  font: inherit;
  font-size: 1rem;
  background: var(--color-surface-raised);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  outline: none;
}

.spell-input-area input:focus,
.conj-input-area input:focus {
  border-color: var(--color-primary);
  box-shadow: 0 0 0 3px var(--color-primary-soft);
}

.spell-input-area button,
.conj-input-area > button {
  min-height: 3.25rem;
  padding: 0 var(--space-4);
  color: var(--color-primary-contrast);
  font: inherit;
  font-size: 0.82rem;
  font-weight: 800;
  background: var(--color-primary);
  border: 0;
  border-radius: var(--radius-md);
  cursor: pointer;
}

.conj-two-inputs {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: var(--space-2);
  width: 100%;
}

.accent-bar {
  display: grid;
  grid-template-columns: repeat(4, minmax(var(--touch-target), 1fr));
  gap: var(--space-2);
  margin: 0;
}

.accent-bar button {
  width: auto;
  min-width: var(--touch-target);
  height: var(--touch-target);
  min-height: var(--touch-target);
  padding: 0;
  color: var(--color-text);
  font: inherit;
  font-size: 0.92rem;
  font-weight: 800;
  background: var(--color-surface-subtle);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  cursor: pointer;
}

.quiz-entry-control:disabled,
.accent-bar button:disabled {
  cursor: not-allowed;
  opacity: 0.48;
}

.quiz-result {
  display: grid;
  justify-items: center;
  padding: clamp(var(--space-6), 8vw, var(--space-9));
  color: var(--color-text);
  text-align: center;
}

.qr-emoji {
  margin-bottom: var(--space-2);
  font-size: clamp(3rem, 14vw, 4.5rem);
  line-height: 1;
}

.quiz-result .quiz-eyebrow {
  margin-bottom: var(--space-1);
}

.qr-title {
  margin: 0;
  font-family: 'Lora', serif;
  font-size: clamp(1.6rem, 7vw, 2.25rem);
  line-height: 1.2;
}

.qr-sub {
  margin: var(--space-2) 0 var(--space-5);
  color: var(--color-text-muted);
  font-size: 0.82rem;
}

.qr-stats {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: var(--space-2);
  width: 100%;
  margin-bottom: var(--space-5);
}

.qrs {
  display: grid;
  gap: var(--space-1);
  min-width: 0;
  padding: var(--space-3) var(--space-2);
  background: var(--color-surface-subtle);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
}

.qrs-n {
  font-family: 'Lora', serif;
  font-size: clamp(1.25rem, 6vw, 1.8rem);
  line-height: 1.1;
}

.qrs-n.g {
  color: var(--color-success);
}

.qrs-n.r {
  color: var(--color-danger);
}

.qrs-n.b {
  color: var(--color-info);
}

.qrs-l {
  color: var(--color-text-muted);
  font-size: 0.68rem;
  letter-spacing: 0.04em;
}

.qr-btns {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: var(--space-2);
  width: 100%;
}

.qr-btn {
  min-height: 3.25rem;
  padding: 0 var(--space-4);
  color: var(--color-text);
  font: inherit;
  font-size: 0.8rem;
  font-weight: 700;
  background: var(--color-surface-subtle);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  cursor: pointer;
}

.qr-btn.primary {
  color: var(--color-primary-contrast);
  background: var(--color-primary);
  border-color: var(--color-primary);
}

.wrong-list {
  width: 100%;
  margin-top: var(--space-6);
  text-align: left;
}

.wl-title {
  display: flex;
  align-items: center;
  gap: var(--space-2);
  margin: 0 0 var(--space-3);
  color: var(--color-text-muted);
  font-size: 0.72rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.wl-title::after {
  height: 1px;
  flex: 1;
  content: '';
  background: var(--color-border);
}

.wrong-item {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: var(--space-1);
  padding: var(--space-3) 0;
  border-bottom: 1px solid var(--color-border);
}

.wi-word {
  color: var(--color-danger);
  font-family: 'Lora', serif;
  font-size: 0.92rem;
  font-weight: 700;
}

.wi-ans {
  color: var(--color-text-muted);
  font-size: 0.74rem;
  line-height: 1.45;
  text-align: left;
}

.quiz-result-success {
  width: 100%;
  margin: var(--space-5) 0 0;
  padding: var(--space-4);
  color: var(--color-success);
  font-size: 0.82rem;
  font-weight: 800;
  background: var(--color-success-soft);
  border-radius: var(--radius-md);
}

@media (hover: hover) {
  .quiz-back-btn:hover,
  .quiz-icon-btn:hover,
  .show-answer-btn:hover,
  .accent-bar button:hover,
  .qr-btn:hover {
    color: var(--color-primary);
    border-color: var(--color-primary);
  }

  .qopt:hover:not(:disabled) {
    background: var(--color-primary-soft);
    border-color: var(--color-primary);
    transform: translateY(-1px);
  }
}

@media (min-width: 600px) {
  .qc-feedback {
    grid-template-columns: minmax(0, 1fr) auto;
    align-items: end;
  }

  .next-btn {
    width: auto;
    min-width: 9rem;
  }

  .spell-input-area,
  .conj-input-area {
    grid-template-columns: minmax(0, 1fr) auto;
  }

  .conj-two-inputs {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .accent-bar {
    grid-template-columns: repeat(7, var(--touch-target));
  }

  .qr-btns {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }

  .wrong-item {
    grid-template-columns: minmax(0, 1fr) minmax(0, 2fr);
    align-items: baseline;
  }

  .wi-ans {
    text-align: right;
  }
}

@media (min-width: 700px) {
  .qc-options {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

@media (prefers-reduced-motion: reduce) {
  .quiz-card,
  .qc-feedback.show {
    animation: none;
  }

  .qc-prog-fill {
    transition: none;
  }
}

/* ===== Stage 5: mobile-first flashcard session ===== */
.visually-hidden {
  position: absolute !important;
  width: 1px !important;
  height: 1px !important;
  padding: 0 !important;
  margin: -1px !important;
  overflow: hidden !important;
  clip: rect(0, 0, 0, 0) !important;
  white-space: nowrap !important;
  border: 0 !important;
}

.flashcard-session {
  width: min(100%, 760px);
  margin: 0 auto;
  overflow: hidden;
  background: var(--color-surface-raised);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-xl);
  box-shadow: var(--elevation-1);
  animation: slideIn var(--duration-standard) var(--ease-standard);
}

.flashcard-progress .flashcard-reviewed {
  color: var(--color-primary);
  font-size: 0.68rem;
  font-weight: 800;
  white-space: nowrap;
}

.flashcard-progress .qc-progress-meta {
  justify-content: flex-start;
  flex-wrap: wrap;
}

.flashcard-progress .flashcard-reviewed {
  margin-left: auto;
}

.study-sync-status {
  display: inline-flex;
  align-items: center;
  min-height: 1.45rem;
  padding: 0.15rem 0.45rem;
  color: var(--color-text-muted);
  font-size: 0.62rem;
  font-weight: 800;
  line-height: 1.1;
  white-space: nowrap;
  background: var(--color-surface-subtle);
  border: 1px solid var(--color-border);
  border-radius: 999px;
}

.study-sync-status[data-sync-state="synced"] {
  color: var(--color-success);
  border-color: color-mix(in srgb, var(--color-success) 35%, var(--color-border));
}

.study-sync-status[data-sync-state="pending"],
.study-sync-status[data-sync-state="syncing"] {
  color: var(--color-primary);
  border-color: color-mix(in srgb, var(--color-primary) 35%, var(--color-border));
}

.study-sync-status[data-sync-state="offline"],
.study-sync-status[data-sync-state="error"] {
  color: var(--color-danger);
  border-color: color-mix(in srgb, var(--color-danger) 35%, var(--color-border));
}

.flashcard-result .study-sync-status {
  margin: 0 auto var(--space-3);
}

.flashcard-stage {
  display: grid;
  gap: var(--space-3);
  padding: clamp(var(--space-4), 5vw, var(--space-7));
}

.flashcard-stage-heading {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-3);
}

.flashcard-stage-heading .qc-type-badge {
  margin: 0;
}

.flashcard-stage-heading .qc-speak {
  flex: 0 0 var(--touch-target);
  width: var(--touch-target);
  padding: 0;
  border-radius: 50%;
}

.flashcard-card-button {
  width: 100%;
  min-height: clamp(19rem, 56vh, 25rem);
  padding: 0;
  color: var(--color-text);
  font: inherit;
  text-align: inherit;
  background: transparent;
  border: 0;
  border-radius: var(--radius-xl);
  cursor: pointer;
  perspective: 1200px;
  touch-action: pan-y;
}

.flashcard-card-inner {
  position: relative;
  display: block;
  width: 100%;
  min-height: inherit;
  transform-style: preserve-3d;
  transition: transform 420ms var(--ease-standard);
}

.flashcard-card-button.is-flipped .flashcard-card-inner {
  transform: rotateY(180deg);
}

.flashcard-face {
  position: absolute;
  inset: 0;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: var(--space-3);
  min-width: 0;
  padding: clamp(var(--space-5), 8vw, var(--space-8));
  overflow: hidden;
  background:
    radial-gradient(circle at top right, color-mix(in srgb, var(--color-primary-soft) 72%, transparent), transparent 42%),
    var(--color-surface-subtle);
  border: 1px solid color-mix(in srgb, var(--color-primary) 26%, var(--color-border));
  border-radius: var(--radius-xl);
  box-shadow: var(--elevation-2);
  backface-visibility: hidden;
  -webkit-backface-visibility: hidden;
}

.flashcard-back {
  background:
    radial-gradient(circle at bottom left, color-mix(in srgb, var(--color-info-soft) 78%, transparent), transparent 48%),
    var(--color-surface-raised);
  transform: rotateY(180deg);
}

.flashcard-face-label {
  color: var(--color-primary);
  font-size: 0.68rem;
  font-weight: 800;
  letter-spacing: 0.12em;
  text-transform: uppercase;
}

.flashcard-face-text {
  max-width: 100%;
  color: var(--color-text);
  font-family: 'Lora', serif;
  font-size: clamp(2rem, 11vw, 4rem);
  font-weight: 700;
  line-height: 1.18;
  text-align: center;
  overflow-wrap: anywhere;
}

.flashcard-face-text.zh {
  font-family: 'Noto Sans SC', sans-serif;
  font-size: clamp(1.25rem, 6vw, 2.15rem);
  line-height: 1.55;
}

.flashcard-face-detail {
  max-width: 100%;
  color: var(--color-text-muted);
  font-family: 'JetBrains Mono', monospace;
  font-size: 0.76rem;
  line-height: 1.5;
  text-align: center;
  overflow-wrap: anywhere;
}

.flashcard-flip-hint {
  position: absolute;
  right: var(--space-4);
  bottom: var(--space-4);
  left: var(--space-4);
  color: var(--color-text-muted);
  font-size: 0.68rem;
  line-height: 1.4;
  text-align: center;
}

.flashcard-study-hint {
  margin: 0;
  color: var(--color-text-muted);
  font-size: 0.68rem;
  line-height: 1.5;
  text-align: center;
}

.flashcard-actions {
  display: grid;
  gap: var(--space-3);
  padding-top: var(--space-2);
}

.flashcard-actions[hidden] {
  display: none;
}

.flashcard-actions-title,
.quiz-wordbook-actions > p {
  margin: 0;
  color: var(--color-text-muted);
  font-size: 0.72rem;
  line-height: 1.5;
}

.wordbook-action-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: var(--space-2);
}

.wordbook-action {
  min-width: 0;
  min-height: var(--touch-target);
  padding: var(--space-2);
  color: var(--color-text);
  font: inherit;
  font-size: 0.7rem;
  font-weight: 800;
  line-height: 1.35;
  text-align: center;
  background: var(--color-surface-subtle);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  cursor: pointer;
  transition:
    background var(--duration-fast) var(--ease-standard),
    border-color var(--duration-fast) var(--ease-standard),
    transform var(--duration-fast) var(--ease-standard);
}

.wordbook-action.is-selected,
.wordbook-action:disabled {
  color: var(--color-success);
  cursor: default;
  background: var(--color-success-soft);
  border-color: color-mix(in srgb, var(--color-success) 35%, var(--color-border));
  opacity: 1;
}

.flashcard-next {
  width: 100%;
  min-height: 3.25rem;
  padding: 0 var(--space-4);
  color: var(--color-primary-contrast);
  font: inherit;
  font-size: 0.82rem;
  font-weight: 800;
  background: var(--color-primary);
  border: 0;
  border-radius: var(--radius-md);
  cursor: pointer;
}

.flashcard-next span {
  font-size: 0.68rem;
  font-weight: 500;
  opacity: 0.84;
}

.quiz-wordbook-actions {
  display: grid;
  gap: var(--space-2);
  padding-top: var(--space-3);
  border-top: 1px solid var(--color-border);
}

.quiz-wordbook-actions[hidden] {
  display: none;
}

.flashcard-result-stats {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: var(--space-2);
  width: 100%;
  margin-bottom: var(--space-5);
}

@media (hover: hover) {
  .wordbook-action:not(:disabled):hover {
    background: var(--color-primary-soft);
    border-color: var(--color-primary);
    transform: translateY(-1px);
  }
}

@media (min-width: 700px) {
  .flashcard-result-stats {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

  .learning-report-grid {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }
}

@media (prefers-reduced-motion: reduce) {
  .flashcard-session {
    animation: none;
  }

  .flashcard-card-inner,
  .wordbook-action {
    transition: none;
  }
}

/* ===== Pre-release learning-path and practice-range clarity ===== */
.learning-path-nav {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: var(--space-3);
}

.learning-path-nav button {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr) auto;
  align-items: center;
  gap: var(--space-3);
  min-height: 5rem;
  padding: var(--space-3) var(--space-4);
  color: var(--color-text);
  font: inherit;
  text-align: left;
  background: var(--color-surface-raised);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  box-shadow: var(--elevation-1);
  cursor: pointer;
}

.learning-path-nav button > span:nth-child(2) {
  display: grid;
  gap: 0.15rem;
}

.learning-path-nav strong {
  font-size: 0.85rem;
}

.learning-path-nav small {
  color: var(--color-text-muted);
  font-size: 0.68rem;
  line-height: 1.45;
}

.learning-path-icon {
  display: grid;
  width: var(--touch-target);
  height: var(--touch-target);
  place-items: center;
  background: var(--color-primary-soft);
  border-radius: var(--radius-md);
}

.learning-textbook-heading {
  padding: clamp(var(--space-4), 4vw, var(--space-6));
  border-bottom: 1px solid var(--color-border);
}

.learning-textbook-heading h2 {
  margin: 0;
  font-family: 'Lora', serif;
  font-size: 1.12rem;
}

#pv-wordbook .pwi2-right {
  display: grid;
  grid-template-columns: repeat(4, minmax(4.25rem, auto));
}

#pv-wordbook .pwi2-acc {
  display: none;
}

#pv-wordbook .pwi2-toggle,
#pv-wordbook .pwi2-toggle.review-btn {
  display: grid;
  grid-template-columns: auto auto;
  align-items: center;
  justify-content: center;
  gap: var(--space-2);
  width: auto;
  min-width: 4.25rem;
  padding: 0 var(--space-2);
  font-size: 0.68rem;
  font-weight: 700;
}

#pv-wordbook .pwi2-toggle strong {
  color: var(--color-text);
  font-size: 0.7rem;
}

#pv-wordbook .pwi2-toggle:disabled {
  cursor: not-allowed;
  opacity: 0.48;
}

.quiz-advanced-heading,
.quiz-selected-heading {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-4);
  min-height: 4.75rem;
  padding: var(--space-3) var(--space-4);
}

.quiz-advanced-heading > span,
.quiz-selected-heading > div {
  display: grid;
  gap: 0.1rem;
}

.quiz-advanced-heading strong,
.quiz-selected-heading h2 {
  margin: 0;
  color: var(--color-text);
  font-size: 0.84rem;
}

.quiz-advanced-heading small,
.quiz-selected-heading p {
  margin: 0;
  color: var(--color-text-muted);
  font-size: 0.68rem;
  line-height: 1.45;
}

.quiz-clear-range,
.quiz-selected-heading button {
  min-height: var(--touch-target);
  padding: 0 var(--space-3);
  color: var(--color-primary);
  font: inherit;
  font-size: 0.7rem;
  font-weight: 800;
  white-space: nowrap;
  background: var(--color-primary-soft);
  border: 1px solid color-mix(in srgb, var(--color-primary) 28%, var(--color-border));
  border-radius: var(--radius-md);
  cursor: pointer;
}

.quiz-selected-heading button:disabled {
  color: var(--color-text-muted);
  cursor: default;
  background: var(--color-surface-subtle);
  border-color: var(--color-border);
}

.quiz-selected-filters {
  overflow: hidden;
  background: var(--color-surface-raised);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
}

.quiz-selected-chip-list {
  display: flex;
  gap: var(--space-2);
  padding: var(--space-3) var(--space-4);
  flex-wrap: wrap;
  background: var(--color-surface-subtle);
  border-top: 1px solid var(--color-border);
}

.quiz-selected-chip {
  display: inline-flex;
  align-items: center;
  gap: var(--space-2);
  min-height: var(--touch-target);
  padding: 0 var(--space-3);
  color: var(--color-primary);
  font: inherit;
  font-size: 0.7rem;
  font-weight: 800;
  background: var(--color-primary-soft);
  border: 1px solid color-mix(in srgb, var(--color-primary) 34%, var(--color-border));
  border-radius: 999px;
  cursor: pointer;
}

.quiz-selected-chip span:last-child {
  font-size: 1rem;
  line-height: 1;
}

.quiz-selected-empty {
  width: 100%;
  margin: 0;
  color: var(--color-text-muted);
  font-size: 0.7rem;
  line-height: 1.5;
}

.qc-progress-actions,
.quiz-question-utility {
  display: flex;
  align-items: center;
  justify-content: flex-end;
  gap: var(--space-2);
}

.qc-question-row .quiz-question-utility {
  flex: 0 0 auto;
}

.quiz-detail-action {
  min-height: var(--touch-target);
  padding: 0 var(--space-3);
  color: var(--color-primary);
  font: inherit;
  font-size: 0.7rem;
  font-weight: 800;
  white-space: nowrap;
  background: var(--color-primary-soft);
  border: 1px solid color-mix(in srgb, var(--color-primary) 30%, var(--color-border));
  border-radius: var(--radius-md);
  cursor: pointer;
}

@media (hover: hover) {
  .learning-path-nav button:hover,
  .quiz-selected-chip:hover,
  .quiz-detail-action:hover {
    border-color: var(--color-primary);
    transform: translateY(-1px);
  }
}

@media (min-width: 700px) {
  .learning-path-nav {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

@media (max-width: 520px) {
  #pv-wordbook .pwi2-right {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    width: 100%;
  }

  #pv-wordbook .pwi2-toggle,
  #pv-wordbook .pwi2-toggle.review-btn {
    grid-template-columns: minmax(0, 1fr);
    gap: 0;
    min-width: 0;
    padding: var(--space-1);
  }

  .quiz-advanced-heading,
  .quiz-selected-heading {
    align-items: stretch;
    flex-direction: column;
  }

  .quiz-clear-range,
  .quiz-selected-heading button {
    width: 100%;
  }

  .qc-progress {
    grid-template-columns: minmax(0, 1fr);
  }

  .qc-progress-actions {
    display: grid;
    grid-template-columns: minmax(0, 1fr) minmax(0, 1fr);
  }

  .quiz-back-btn {
    margin-left: 0;
  }
}