/* =========================================================
   408知识点速过 · UI v3 精致版
   视觉：更亮青绿 + 软玻璃感 + 重点高亮 + 清晰层次
   ========================================================= */

:root {
  --bg: #f0f4f2;
  --bg-2: #e7efeb;
  --card: #ffffff;
  --ink: #0f1c17;
  --ink-2: #2f3f38;
  --muted: #6d7f76;
  --line: #dde8e2;
  --primary: #0d9488;
  --primary-2: #0f766e;
  --primary-soft: #e0f5f1;
  --primary-ink: #0a5c54;
  --accent: #14b8a6;
  --danger: #e11d48;
  --danger-soft: #fff0f3;
  --warn: #d97706;
  --warn-soft: #fff7ed;
  --ok: #059669;
  --ok-soft: #ecfdf5;
  --star: #ca8a04;
  --star-soft: #fef9c3;
  --violet: #7c3aed;
  --violet-soft: #f3f0ff;
  --blue: #2563eb;
  --blue-soft: #eff6ff;
  --radius: 18px;
  --radius-sm: 12px;
  --radius-xs: 8px;
  --shadow: 0 1px 2px rgba(15, 40, 30, .04), 0 8px 24px rgba(15, 40, 30, .06);
  --shadow-lg: 0 4px 12px rgba(15, 40, 30, .06), 0 16px 40px rgba(15, 40, 30, .08);
  --tabbar-h: 68px;
  --topbar-h: 56px;
  --font: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Microsoft YaHei", sans-serif;
  --mono: ui-monospace, "SF Mono", "Cascadia Code", Consolas, monospace;
  --topbar-bg: rgba(240, 244, 242, .9);
  --code-bg: #eef3f1;
  --stage-bg: #f7faf8;
  --grad: linear-gradient(135deg, #0d9488 0%, #0f766e 55%, #115e59 100%);
  --grad-soft: linear-gradient(180deg, #e0f5f1 0%, #f0f4f2 100%);
}

[data-theme="dark"] {
  --bg: #0f1412;
  --bg-2: #161c19;
  --card: #1a221e;
  --ink: #e8f0ec;
  --ink-2: #c5d4cc;
  --muted: #8aa096;
  --line: #2a3630;
  --primary: #2dd4bf;
  --primary-2: #14b8a6;
  --primary-soft: #12352f;
  --primary-ink: #5eead4;
  --accent: #5eead4;
  --danger: #fb7185;
  --danger-soft: #3a1a22;
  --warn: #fbbf24;
  --warn-soft: #3a2e14;
  --ok: #34d399;
  --ok-soft: #12352a;
  --star: #facc15;
  --star-soft: #3a3210;
  --violet: #a78bfa;
  --violet-soft: #2a2140;
  --blue: #60a5fa;
  --blue-soft: #1a2740;
  --shadow: 0 1px 2px rgba(0,0,0,.2), 0 8px 24px rgba(0,0,0,.18);
  --shadow-lg: 0 4px 12px rgba(0,0,0,.2), 0 16px 40px rgba(0,0,0,.22);
  --topbar-bg: rgba(15, 20, 18, .88);
  --code-bg: #243029;
  --stage-bg: #141a17;
  --grad: linear-gradient(135deg, #0f766e 0%, #115e59 55%, #134e4a 100%);
  --grad-soft: linear-gradient(180deg, #12352f 0%, #0f1412 100%);
}

[data-theme="dark"] .chip.muted { background: #2a3630; color: var(--muted); }
[data-theme="dark"] .chip.demo { background: var(--blue-soft); color: var(--blue); }
[data-theme="dark"] .chip.star { background: var(--star-soft); color: var(--star); }
[data-theme="dark"] .banner.info { background: var(--primary-soft); color: var(--primary-ink); }
[data-theme="dark"] .banner.warn { background: var(--warn-soft); color: var(--warn); }
[data-theme="dark"] .tip-box { background: var(--warn-soft); }
[data-theme="dark"] .mnem-box,
[data-theme="dark"] .explain { background: var(--primary-soft); }
[data-theme="dark"] .stage { background: var(--stage-bg); }
[data-theme="dark"] code, [data-theme="dark"] .code { background: var(--code-bg); color: #d5e4dc; }
[data-theme="dark"] .q-hint { background: #141a17; color: var(--muted); }
[data-theme="dark"] .metric { background: #141a17; border-color: var(--line); }
[data-theme="dark"] .seg { background: #141a17; }
[data-theme="dark"] .seg button.on { background: var(--card); color: var(--ink); }
[data-theme="dark"] .overlay { background: rgba(0,0,0,.6); }
[data-theme="dark"] .flash,
[data-theme="dark"] .player,
[data-theme="dark"] .topbar,
[data-theme="dark"] .tabbar { background: var(--card); }
[data-theme="dark"] .topbar { background: var(--topbar-bg); }
[data-theme="dark"] .tabbar { background: rgba(26, 34, 30, .96); }
[data-theme="dark"] input,
[data-theme="dark"] select,
[data-theme="dark"] textarea { background: #141a17; color: var(--ink); border-color: var(--line); }
[data-theme="dark"] .steps li code,
[data-theme="dark"] .flash-a code { background: var(--code-bg); }
[data-theme="dark"] table.data-t th { background: #243029; }
[data-theme="dark"] .empty { color: var(--muted); }
[data-theme="dark"] .hero { background: var(--grad); }
[data-theme="dark"] .subj-icon.ds { background: #0f766e; }
[data-theme="dark"] .subj-icon.os { background: #2563eb; }
[data-theme="dark"] .subj-icon.cn { background: #ea580c; }
[data-theme="dark"] .subj-icon.co { background: #7c3aed; }
[data-theme="dark"] .grade-btn.no { background: var(--card); border-color: #7f1d1d; color: #fca5a5; }
[data-theme="dark"] .grade-btn.vague { background: var(--card); border-color: #92400e; color: #fcd34d; }
[data-theme="dark"] .grade-btn.yes { background: var(--card); border-color: #065f46; color: #6ee7b7; }

* { box-sizing: border-box; -webkit-tap-highlight-color: transparent; }
html, body { margin: 0; padding: 0; min-height: 100%; }
body {
  font-family: var(--font);
  background: var(--bg);
  color: var(--ink);
  font-size: 15px;
  line-height: 1.6;
  overflow-x: hidden;
  -webkit-font-smoothing: antialiased;
}
button { font-family: inherit; cursor: pointer; border: none; background: none; color: inherit; }
a { color: var(--primary); text-decoration: none; }
code, .mono {
  font-family: var(--mono);
  font-size: .9em;
  background: var(--code-bg);
  padding: 2px 6px;
  border-radius: 6px;
}
.hl { color: var(--primary); font-weight: 700; }

/* —— 顶栏 —— */
.topbar {
  position: sticky; top: 0; z-index: 40;
  display: flex; align-items: center; gap: 8px;
  height: var(--topbar-h);
  padding: 0 12px;
  background: var(--topbar-bg);
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
  border-bottom: 1px solid transparent;
}
.topbar.scrolled { border-bottom-color: var(--line); }
.topbar-main { flex: 1; min-width: 0; }
.topbar h1 { margin: 0; font-size: 17px; font-weight: 800; letter-spacing: .2px; }
.topbar-sub { margin: 1px 0 0; font-size: 12px; color: var(--muted); }
.topbar-extra { display: flex; align-items: center; gap: 6px; }
.icon-btn {
  width: 36px; height: 36px; border-radius: 10px;
  display: grid; place-items: center; color: var(--ink);
  flex-shrink: 0;
}
.icon-btn:active { background: rgba(0,0,0,.05); }

/* —— 主区 —— */
.view {
  min-height: calc(100vh - var(--topbar-h) - var(--tabbar-h) - 12px);
  padding: 12px 14px calc(var(--tabbar-h) + 28px);
  max-width: 920px;
  margin: 0 auto;
}
.view.no-tabbar {
  padding-bottom: 32px;
  min-height: calc(100vh - var(--topbar-h));
}

/* —— 底栏 —— */
.tabbar {
  position: fixed; left: 0; right: 0; bottom: 0; z-index: 50;
  display: grid; grid-template-columns: repeat(4, 1fr);
  height: calc(var(--tabbar-h) + env(safe-area-inset-bottom));
  padding-bottom: env(safe-area-inset-bottom);
  background: rgba(255,255,255,.96);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border-top: 1px solid var(--line);
}
.tabbar[hidden] { display: none; }
.tab {
  display: flex; flex-direction: column; align-items: center; justify-content: center; gap: 3px;
  color: var(--muted); font-size: 11px; font-weight: 700;
  position: relative;
}
.tab svg { width: 22px; height: 22px; }
.tab.on { color: var(--primary); }
.tab.on::before {
  content: '';
  position: absolute; top: 0;
  width: 28px; height: 3px; border-radius: 0 0 3px 3px;
  background: var(--primary);
}

/* —— 按钮 —— */
.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: 6px;
  min-height: 44px; padding: 0 18px;
  border-radius: var(--radius-sm);
  background: var(--card);
  border: 1px solid var(--line);
  font-weight: 700; font-size: 14px;
  color: var(--ink);
  transition: transform .12s, box-shadow .12s;
}
.btn:active { transform: scale(.97); }
.btn.primary {
  background: var(--grad);
  color: #fff; border-color: transparent;
  box-shadow: 0 4px 14px rgba(13, 148, 136, .28);
}
.btn.primary:active { box-shadow: 0 2px 8px rgba(13, 148, 136, .22); }
.btn.ghost { background: transparent; border-color: var(--line); }
.btn.danger { background: var(--danger-soft); color: var(--danger); border-color: transparent; }
.btn.block { width: 100%; }
.btn.sm { min-height: 34px; padding: 0 12px; font-size: 13px; border-radius: 10px; }

.sec-title {
  margin: 20px 4px 10px;
  font-size: 13px; font-weight: 800; color: var(--muted);
  letter-spacing: .6px;
  text-transform: uppercase;
}

/* —— 标签 —— */
.chip {
  display: inline-flex; align-items: center;
  padding: 3px 9px; border-radius: 999px;
  font-size: 12px; font-weight: 700;
  background: var(--primary-soft); color: var(--primary-ink);
}
.chip.muted { background: #eef2f0; color: var(--muted); }
.chip.warn { background: var(--warn-soft); color: var(--warn); }
.chip.star { background: var(--star-soft); color: var(--star); }
.chip.demo { background: var(--blue-soft); color: var(--blue); }

.banner {
  border-radius: var(--radius-sm);
  padding: 12px 14px;
  font-size: 13.5px;
  margin-bottom: 12px;
  line-height: 1.55;
}
.banner.info { background: var(--primary-soft); color: var(--primary-ink); }
.banner.warn { background: var(--warn-soft); color: #9a5b00; }

/* =========================================================
   动画：进场 / 翻转 / 反馈
   ========================================================= */
@keyframes fadeUp {
  from { opacity: 0; transform: translateY(10px); }
  to { opacity: 1; transform: translateY(0); }
}
@keyframes fadeIn {
  from { opacity: 0; }
  to { opacity: 1; }
}
@keyframes popIn {
  0% { opacity: 0; transform: scale(.96); }
  60% { transform: scale(1.01); }
  100% { opacity: 1; transform: scale(1); }
}
@keyframes slideIn {
  from { opacity: 0; transform: translateX(16px); }
  to { opacity: 1; transform: translateX(0); }
}
@keyframes pulseBar {
  0% { transform: scaleX(.98); }
  50% { transform: scaleX(1); }
  100% { transform: scaleX(.98); }
}

.view > * { animation: fadeUp .28s ease both; }
.view > *:nth-child(2) { animation-delay: .04s; }
.view > *:nth-child(3) { animation-delay: .08s; }
.view > *:nth-child(4) { animation-delay: .12s; }

.hero { animation: popIn .35s ease both; }
.subj-card, .quick-btn, .chap-item, .viz-card, .result-item {
  animation: fadeUp .28s ease both;
  transition: transform .18s ease, box-shadow .18s ease, border-color .18s ease;
}
.subj-card:hover, .quick-btn:hover, .viz-card:hover, .result-item:hover {
  transform: translateY(-1px);
  box-shadow: var(--shadow-lg);
}
.chap-item { transition: box-shadow .2s ease; }
.chap-body { animation: fadeIn .2s ease; }

.point-card { animation: popIn .3s ease both; }
.point-card h2 { animation: fadeIn .35s ease .05s both; }
.answer-block.show { animation: fadeUp .28s ease both; }
.steps li { animation: fadeUp .24s ease both; }
.steps li:nth-child(1) { animation-delay: .02s; }
.steps li:nth-child(2) { animation-delay: .06s; }
.steps li:nth-child(3) { animation-delay: .1s; }
.tip-box, .mnem-box { animation: slideIn .28s ease .1s both; }

.flash {
  animation: popIn .3s ease both;
  transition: transform .18s ease, box-shadow .18s ease;
}
.flash.flipped { animation: popIn .22s ease; }
.flash.flipped .flash-a { animation: fadeUp .28s ease both; }
.grade-btn { transition: transform .12s ease, box-shadow .18s ease, background .18s ease; }
.grade-btn:hover:not(:disabled) { transform: translateY(-1px); box-shadow: var(--shadow-lg); }
.grade-btn:active:not(:disabled) { transform: scale(.96); }

.player { animation: fadeUp .28s ease both; }
.stage { animation: fadeIn .22s ease; }
.explain { animation: slideIn .24s ease; }
.metric { animation: fadeUp .22s ease both; }
.drill-progress i { transition: width .4s cubic-bezier(.22, 1, .36, 1); }
.bar-fill { transition: width .45s cubic-bezier(.22, 1, .36, 1); }

.side-btn { transition: background .16s ease, color .16s ease, border-color .16s ease, transform .12s ease; }
.side-btn:active:not(:disabled) { transform: scale(.96); }
.btn { transition: transform .12s ease, box-shadow .16s ease, background .16s ease; }
.btn:active { transform: scale(.97); }
.tab { transition: color .16s ease; }
.tab.on::before { transition: width .2s ease; }

.viz-list .viz-card { animation: fadeUp .26s ease both; }
.viz-list .viz-card:nth-child(odd) { animation-delay: .03s; }
.viz-list .viz-card:nth-child(even) { animation-delay: .07s; }

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation-duration: .01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: .01ms !important;
  }
}

/* —— 首页 hero —— */
.hero {
  background: var(--grad);
  border-radius: 22px;
  color: #fff;
  padding: 22px 20px 18px;
  display: grid; gap: 14px;
  box-shadow: 0 8px 28px rgba(13, 148, 136, .28);
  position: relative;
  overflow: hidden;
}
.hero::after {
  content: '';
  position: absolute; right: -40px; top: -40px;
  width: 160px; height: 160px; border-radius: 50%;
  background: rgba(255,255,255,.08);
  pointer-events: none;
}
.hero-top { display: flex; align-items: center; gap: 16px; position: relative; z-index: 1; }
.ring {
  --pct: 0%;
  width: 92px; height: 92px; border-radius: 50%; flex-shrink: 0;
  background: conic-gradient(#fff var(--pct), rgba(255,255,255,.22) 0);
  display: grid; place-items: center;
  box-shadow: 0 0 0 4px rgba(255,255,255,.15);
}
.ring-in {
  width: 76px; height: 76px; border-radius: 50%;
  background: var(--primary-2);
  display: flex; flex-direction: column; align-items: center; justify-content: center;
  color: #fff;
}
.ring-n { font-size: 20px; font-weight: 800; line-height: 1.1; }
.ring-l { font-size: 10px; opacity: .85; }
.hero-info { flex: 1; min-width: 0; }
.hero-row { display: flex; flex-wrap: wrap; gap: 4px 14px; font-size: 14px; align-items: baseline; }
.hero-row b { font-size: 22px; font-weight: 800; }
.hero-row span { opacity: .85; margin-right: 2px; font-size: 13px; }
.hero-sub { margin-top: 4px; font-size: 12.5px; opacity: .85; }
.hero-streak { margin-top: 6px; font-size: 13px; font-weight: 700; }
.hero-go {
  width: 100%; min-height: 52px; font-size: 16px; border-radius: 16px;
  background: #fff; color: var(--primary-2); border: none;
  box-shadow: 0 4px 16px rgba(0,0,0,.12);
  position: relative; z-index: 1;
}
.hero-plan {
  margin-top: 2px; font-size: 13px; text-align: center; opacity: .9;
  position: relative; z-index: 1;
}

/* 引导 */
.guide {
  margin-top: 12px; background: var(--card);
  border-radius: var(--radius); box-shadow: var(--shadow);
  overflow: hidden; border: 1px solid var(--line);
}
.guide-head {
  width: 100%; display: flex; align-items: center; gap: 8px;
  padding: 14px 16px; font-weight: 800; font-size: 15px;
}
.guide-title { flex: 1; text-align: left; }
.guide-caret { color: var(--muted); transition: transform .2s; }
.guide.open .guide-caret { transform: rotate(180deg); }
.guide-body { display: none; padding: 0 16px 16px; }
.guide.open .guide-body { display: block; }
.guide-steps { display: grid; gap: 12px; }
.guide-step { display: flex; gap: 10px; }
.gs-n {
  width: 22px; height: 22px; border-radius: 50%; flex-shrink: 0;
  background: var(--primary); color: #fff;
  font-size: 12px; font-weight: 800;
  display: grid; place-items: center; margin-top: 2px;
}
.gs-body { display: grid; gap: 2px; }
.gs-body b { font-size: 14px; }
.gs-body span { font-size: 13px; color: var(--muted); }
.guide-go { display: flex; gap: 10px; margin-top: 14px; flex-wrap: wrap; }

/* 科目卡 */
.subj-list { display: grid; grid-template-columns: 1fr 1fr; gap: 10px; }
@media (max-width: 520px) { .subj-list { grid-template-columns: 1fr; } }
.subj-card {
  display: flex; align-items: center; gap: 12px;
  background: var(--card); border-radius: var(--radius);
  box-shadow: var(--shadow); border: 1px solid var(--line);
  padding: 16px; text-align: left; width: 100%;
  transition: transform .16s ease, box-shadow .16s ease, border-color .16s ease;
  position: relative; overflow: hidden;
}
.subj-card::after {
  content: '';
  position: absolute; left: 0; top: 0; bottom: 0; width: 3px;
  background: transparent; transition: background .16s ease;
}
.subj-card:active { transform: scale(.985); box-shadow: var(--shadow-lg); }
.subj-icon {
  width: 46px; height: 46px; border-radius: 14px; flex-shrink: 0;
  display: grid; place-items: center;
  font-weight: 800; font-size: 17px; color: #fff;
  box-shadow: 0 4px 12px rgba(0,0,0,.12);
}
.subj-icon.ds { background: linear-gradient(135deg,#0d9488,#0f766e); }
.subj-icon.os { background: linear-gradient(135deg,#3b82f6,#2563eb); }
.subj-icon.cn { background: linear-gradient(135deg,#fb923c,#ea580c); }
.subj-icon.co { background: linear-gradient(135deg,#a78bfa,#7c3aed); }
.subj-main { flex: 1; min-width: 0; display: grid; gap: 3px; }
.subj-name { font-weight: 800; font-size: 15px; }
.subj-meta { font-size: 12px; color: var(--muted); }
.bar { height: 6px; border-radius: 99px; background: var(--bg-2); overflow: hidden; margin-top: 4px; }
.bar-fill { display: block; height: 100%; background: var(--grad); border-radius: 99px; transition: width .45s cubic-bezier(.22, 1, .36, 1); }
.subj-pct { font-weight: 800; font-size: 15px; color: var(--primary); }

/* 快捷 */
.quick-list { display: grid; grid-template-columns: repeat(auto-fill, minmax(140px, 1fr)); gap: 10px; }
.quick-btn {
  display: flex; align-items: center; gap: 10px;
  background: var(--card); border-radius: var(--radius-sm);
  box-shadow: var(--shadow); border: 1px solid var(--line);
  padding: 14px 12px; font-weight: 700; font-size: 14px; text-align: left;
}
.quick-btn:active { transform: scale(.98); }
.quick-ico { font-size: 18px; line-height: 1; }

/* —— 章节 —— */
.chap-list { display: grid; gap: 10px; }
.chap-item {
  background: var(--card); border-radius: var(--radius);
  box-shadow: var(--shadow); overflow: hidden; border: 1px solid var(--line);
}
.chap-head {
  width: 100%; display: flex; align-items: center; gap: 10px;
  padding: 14px; text-align: left;
}
.chap-n {
  width: 30px; height: 30px; border-radius: 9px;
  background: var(--primary-soft); color: var(--primary-ink);
  font-size: 12px; font-weight: 800;
  display: grid; place-items: center; flex-shrink: 0;
}
.chap-t { flex: 1; font-weight: 800; font-size: 14.5px; }
.chap-meta { font-size: 12px; color: var(--muted); }
.chap-caret { color: var(--muted); transition: transform .18s; font-size: 12px; }
.chap-item.open .chap-caret { transform: rotate(180deg); }
.chap-body { display: none; border-top: 1px solid var(--line); }
.chap-item.open .chap-body { display: block; }
.point-row {
  width: 100%; display: flex; align-items: flex-start; gap: 8px;
  padding: 12px 14px; text-align: left;
  border-bottom: 1px solid var(--line);
}
.point-row:last-child { border-bottom: none; }
.point-row:active { background: var(--bg-2); }
.point-t { flex: 1; font-size: 14px; font-weight: 500; }
.point-tags { display: flex; gap: 4px; flex-wrap: wrap; margin-top: 4px; }

/* —— 知识点详情 —— */
.point-detail { display: grid; gap: 12px; }

.side-rail {
  display: grid;
  grid-template-columns: 56px 1fr 56px;
  gap: 8px;
  align-items: stretch;
}
.side-btn {
  min-height: 120px;
  border-radius: var(--radius);
  border: 1px dashed var(--line);
  background: var(--card);
  color: var(--muted);
  display: flex; flex-direction: column;
  align-items: center; justify-content: center; gap: 6px;
  font-size: 11px; font-weight: 700;
  transition: background .15s, color .15s, border-color .15s;
}
.side-btn:hover:not(:disabled) {
  background: var(--primary-soft);
  color: var(--primary-ink);
  border-style: solid;
  border-color: var(--primary);
}
.side-btn:disabled { opacity: .35; cursor: default; }
.side-btn .arr { font-size: 22px; line-height: 1; font-weight: 400; }
@media (max-width: 560px) {
  .side-rail { grid-template-columns: 40px 1fr 40px; }
  .side-btn { min-height: 96px; font-size: 0; gap: 0; }
  .side-btn .arr { font-size: 20px; }
}

.point-card {
  background: var(--card);
  border-radius: 20px;
  box-shadow: var(--shadow-lg);
  border: 1px solid var(--line);
  padding: 20px 18px;
  position: relative;
  overflow: hidden;
}
.point-card::before {
  content: '';
  position: absolute; left: 0; top: 0; bottom: 0;
  width: 4px;
  background: var(--grad);
  opacity: .9;
}
.point-card::after {
  content: '';
  position: absolute; right: -30px; top: -30px;
  width: 120px; height: 120px; border-radius: 50%;
  background: var(--primary-soft);
  opacity: .55; pointer-events: none;
}
.point-card h2 {
  margin: 10px 0 0;
  font-size: 18px;
  line-height: 1.45;
  font-weight: 800;
  position: relative; z-index: 1;
}
.point-card .q-hint {
  margin: 14px 0 0;
  text-align: center; color: var(--muted); font-size: 13px;
  padding: 14px; border-radius: 12px;
  background: var(--bg-2);
  border: 1px dashed var(--line);
  cursor: pointer;
}
.answer-block { display: none; margin-top: 14px; }
.answer-block.show { display: block; }
.answer-block h3 {
  margin: 0 0 10px; font-size: 14px; font-weight: 800;
  padding-bottom: 8px;
  border-bottom: 1px dashed var(--line);
  color: var(--primary-ink);
}
.steps { margin: 0; padding-left: 0; list-style: none; display: grid; gap: 10px; }
.steps li {
  position: relative; padding-left: 30px;
  font-size: 14.5px; line-height: 1.65;
}
.steps li::before {
  content: attr(data-i);
  position: absolute; left: 0; top: 2px;
  width: 22px; height: 22px; border-radius: 7px;
  background: var(--primary-soft); color: var(--primary-ink);
  font-size: 11px; font-weight: 800;
  display: grid; place-items: center;
}
.steps li .hl { color: var(--primary); font-weight: 700; }
.steps li code { background: var(--code-bg); padding: 1px 5px; border-radius: 4px; }

.tip-box {
  margin-top: 14px; padding: 12px 14px;
  border-left: 3px solid var(--warn);
  background: var(--warn-soft);
  border-radius: 0 12px 12px 0;
  font-size: 13.5px;
  line-height: 1.55;
}
.tip-box b { color: var(--warn); }
.mnem-box {
  margin-top: 10px; padding: 12px 14px;
  border-left: 3px solid var(--violet);
  background: var(--violet-soft);
  border-radius: 0 12px 12px 0;
  font-size: 13.5px;
}
.mnem-box b { color: var(--violet); }
.point-actions { display: flex; gap: 8px; flex-wrap: wrap; margin-top: 14px; }

/* —— 刷卡 —— */
.drill-wrap { display: grid; gap: 14px; max-width: 720px; margin: 0 auto; }
.drill-stat { display: flex; gap: 10px; align-items: center; }
.drill-progress {
  height: 6px; background: var(--bg-2); border-radius: 99px; overflow: hidden; flex: 1;
}
.drill-progress i { display: block; height: 100%; background: var(--grad); border-radius: 99px; transition: width .25s; }
.drill-count { font-weight: 800; color: var(--ink); font-size: 12px; white-space: nowrap; }

.flash {
  background: var(--card);
  border-radius: 22px;
  box-shadow: var(--shadow-lg);
  border: 1px solid var(--line);
  padding: 28px 20px;
  min-height: 220px;
  cursor: pointer; user-select: none;
  display: flex; flex-direction: column; justify-content: center;
  transition: transform .18s ease, box-shadow .18s ease;
  position: relative;
  overflow: hidden;
}
.flash::before {
  content: '';
  position: absolute; inset: 0 0 auto 0; height: 4px;
  background: var(--grad);
}
.flash::after {
  content: '';
  position: absolute; right: -40px; bottom: -40px;
  width: 140px; height: 140px; border-radius: 50%;
  background: var(--primary-soft);
  opacity: .4; pointer-events: none;
}
.flash:active { transform: scale(.99); }
.flash-tags { display: flex; gap: 6px; flex-wrap: wrap; margin-bottom: 14px; }
.flash-q {
  font-size: 22px; font-weight: 800; line-height: 1.4;
  letter-spacing: .2px;
}
.flash-hint {
  margin-top: 18px; text-align: center; color: var(--muted); font-size: 13px;
}
.flash-a { display: none; }
.flash.flipped .flash-q { font-size: 15px; font-weight: 700; margin-bottom: 4px; }
.flash.flipped .flash-hint { display: none; }
.flash.flipped .flash-a { display: block; }
.flash-flipbar {
  margin-top: 16px; padding-top: 12px; border-top: 1px dashed var(--line);
  text-align: center; color: var(--muted); font-size: 12.5px;
}

.grade-row { display: grid; grid-template-columns: 1fr 1fr 1fr; gap: 10px; }
.grade-btn {
  min-height: 68px; border-radius: 16px;
  display: flex; flex-direction: column; align-items: center; justify-content: center; gap: 2px;
  border: 2px solid transparent; background: var(--card);
  box-shadow: var(--shadow);
  transition: transform .12s, box-shadow .12s;
}
.grade-btn b { font-size: 15px; }
.grade-btn span { font-size: 11px; color: var(--muted); }
.grade-btn.no { color: var(--danger); border-color: #fecdd3; background: var(--danger-soft); }
.grade-btn.vague { color: var(--warn); border-color: #fed7aa; background: var(--warn-soft); }
.grade-btn.yes { color: var(--ok); border-color: #a7f3d0; background: var(--ok-soft); }
.grade-btn:active { transform: scale(.97); }
.grade-btn[disabled] { opacity: .4; pointer-events: none; }
.drill-tip { text-align: center; font-size: 12px; color: var(--muted); }

/* —— 演示播放器 —— */
.viz-list { display: grid; grid-template-columns: 1fr 1fr; gap: 10px; }
@media (max-width: 640px) { .viz-list { grid-template-columns: 1fr; } }
.viz-card {
  background: var(--card); border-radius: var(--radius);
  box-shadow: var(--shadow); border: 1px solid var(--line);
  padding: 16px; text-align: left; display: grid; gap: 8px;
  transition: transform .16s ease, box-shadow .16s ease, border-color .16s ease;
  position: relative; overflow: hidden;
}
.viz-card::after {
  content: '';
  position: absolute; left: 0; top: 0; bottom: 0; width: 3px;
  background: var(--primary); opacity: 0; transition: opacity .16s ease;
}
.viz-card:active { transform: scale(.985); box-shadow: var(--shadow-lg); }
.viz-card:hover { border-color: var(--primary); }
.viz-card:hover::after { opacity: 1; }
.viz-n {
  width: 26px; height: 26px; border-radius: 8px;
  background: var(--primary-soft); color: var(--primary-ink);
  font-size: 11px; font-weight: 800;
  display: grid; place-items: center;
}
.viz-card h3 { margin: 0; font-size: 15px; font-weight: 800; }
.viz-card p {
  margin: 0; font-size: 13px; color: var(--muted);
  border-left: 3px solid var(--primary);
  padding-left: 10px; line-height: 1.5;
}

.player {
  background: var(--card);
  border-radius: 18px;
  box-shadow: var(--shadow);
  border: 1px solid var(--line);
  padding: 14px;
}
.player-bar { display: flex; flex-wrap: wrap; align-items: center; gap: 8px; }
.player-bar .btn.primary { min-width: 88px; }
.player-bar .range { flex: 1; min-width: 120px; }
.player-bar .step-n { font-size: 12px; color: var(--muted); font-weight: 700; white-space: nowrap; }
.stage {
  margin-top: 12px;
  min-height: 180px;
  border-radius: 14px;
  background: var(--stage-bg);
  padding: 14px;
  overflow: auto;
  border: 1px solid var(--line);
}
.explain {
  margin-top: 10px;
  padding: 12px 14px;
  border-left: 3px solid var(--primary);
  background: var(--primary-soft);
  border-radius: 0 12px 12px 0;
  font-size: 13.5px;
  min-height: 44px;
  line-height: 1.55;
}
.metrics {
  display: grid; grid-template-columns: repeat(auto-fit, minmax(100px, 1fr));
  gap: 8px; margin-top: 10px;
}
.metric {
  background: var(--card); border: 1px solid var(--line);
  border-radius: 12px; padding: 10px 8px; text-align: center;
}
.metric b { display: block; font-size: 16px; font-weight: 800; }
.metric span { font-size: 11px; color: var(--muted); }

.legend {
  display: flex; flex-wrap: wrap; gap: 10px; margin-top: 10px;
  font-size: 12px; color: var(--muted);
}
.legend i {
  display: inline-block; width: 10px; height: 10px; border-radius: 3px;
  margin-right: 4px; vertical-align: -1px;
}

/* —— 搜索 —— */
.search-box { display: flex; gap: 8px; margin-bottom: 12px; }
.search-box input {
  flex: 1; min-height: 46px; border-radius: 14px;
  border: 1px solid var(--line); background: var(--card);
  padding: 0 16px; font-size: 15px; outline: none;
  font-family: inherit;
}
.search-box input:focus {
  border-color: var(--primary);
  box-shadow: 0 0 0 3px var(--primary-soft);
}
.result-list { display: grid; gap: 8px; }
.result-item {
  background: var(--card); border-radius: var(--radius-sm);
  box-shadow: var(--shadow); border: 1px solid var(--line);
  padding: 14px; text-align: left; width: 100%;
}
.result-item b { display: block; font-size: 14.5px; }
.result-item span { font-size: 12px; color: var(--muted); }

/* —— 设置 / 统计 —— */
.set-list { display: grid; gap: 10px; }
.set-row {
  background: var(--card); border-radius: var(--radius-sm);
  box-shadow: var(--shadow); border: 1px solid var(--line);
  padding: 14px 16px; display: flex; align-items: center; gap: 12px;
}
.set-row .lbl { flex: 1; font-weight: 700; font-size: 14px; }
.set-row .val { font-size: 13px; color: var(--muted); }
.stat-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 10px; }
.stat-card {
  background: var(--card); border-radius: var(--radius);
  box-shadow: var(--shadow); border: 1px solid var(--line);
  padding: 18px; text-align: center;
}
.stat-card b { display: block; font-size: 24px; font-weight: 800; color: var(--primary); }
.stat-card span { font-size: 12px; color: var(--muted); }

/* —— 浮层 —— */
.toast {
  position: fixed; left: 50%; bottom: calc(var(--tabbar-h) + 20px);
  transform: translateX(-50%);
  z-index: 80;
  background: rgba(15, 25, 20, .92); color: #fff;
  padding: 10px 18px; border-radius: 12px;
  font-size: 13.5px; font-weight: 700;
  max-width: 90vw; text-align: center;
}
.toast[hidden] { display: none; }
.overlay {
  position: fixed; inset: 0; z-index: 90;
  background: rgba(15, 25, 20, .4);
  display: grid; place-items: center;
}
.overlay[hidden] { display: none; }
.overlay-card {
  background: var(--card); border-radius: 16px; padding: 22px 28px;
  text-align: center; min-width: 140px;
}
.spinner {
  width: 28px; height: 28px; margin: 0 auto 10px;
  border: 3px solid var(--line); border-top-color: var(--primary);
  border-radius: 50%;
  animation: spin .8s linear infinite;
}
@keyframes spin { to { transform: rotate(360deg); } }

.offline-bar {
  position: fixed; left: 12px; right: 12px;
  bottom: calc(var(--tabbar-h) + 12px);
  z-index: 55;
  background: #15201c; color: #fff;
  padding: 10px 14px; border-radius: 12px;
  font-size: 13px; text-align: center;
}
.offline-bar[hidden] { display: none; }

.empty {
  text-align: center; color: var(--muted);
  padding: 48px 16px; font-size: 14px;
}

/* 演示内部 */
.seg {
  display: inline-flex; background: var(--bg-2); border-radius: 12px; padding: 3px;
  gap: 2px; flex-wrap: wrap;
}
.seg button {
  padding: 7px 14px; border-radius: 9px; font-size: 12.5px; font-weight: 700;
  color: var(--muted);
}
.seg button.on {
  background: var(--card); color: var(--ink);
  box-shadow: 0 1px 3px rgba(0,0,0,.08);
}

.field { display: grid; gap: 4px; margin-top: 10px; }
.field label { font-size: 12px; color: var(--muted); font-weight: 700; }
.field input, .field select, .field textarea {
  min-height: 42px; border-radius: 12px; border: 1px solid var(--line);
  padding: 8px 12px; font-size: 14px; outline: none;
  font-family: inherit; background: var(--card);
}
.field input:focus, .field textarea:focus {
  border-color: var(--primary);
  box-shadow: 0 0 0 3px var(--primary-soft);
}

.bits { display: flex; flex-wrap: wrap; gap: 3px; margin-top: 8px; }
.bit {
  width: 28px; height: 32px; border-radius: 5px;
  display: grid; place-items: center;
  font-family: var(--mono); font-size: 13px; font-weight: 700;
  background: var(--bg-2); color: var(--ink);
}
.bit.on-s { background: var(--violet); color: #fff; }
.bit.on-e { background: var(--blue); color: #fff; }
.bit.on-m { background: var(--primary); color: #fff; }
.bit.hl { outline: 2px solid #e8a317; }

.gantt { display: grid; gap: 4px; }
.gantt-row { display: flex; align-items: center; gap: 6px; font-size: 12px; }
.gantt-lbl { width: 56px; font-weight: 700; flex-shrink: 0; }
.gantt-cells { display: flex; gap: 2px; flex-wrap: wrap; }
.gcell {
  width: 22px; height: 22px; border-radius: 4px;
  background: var(--bg-2); display: grid; place-items: center;
  font-size: 10px; font-weight: 700; color: var(--muted);
}
.gcell.run { background: var(--primary); color: #fff; }
.gcell.wait { background: #f0d4b0; color: #8a5418; }

.tree-svg, .net-svg, .mem-svg { width: 100%; height: auto; max-width: 100%; }

table.data-t {
  width: 100%; border-collapse: collapse; font-size: 12.5px;
  margin-top: 8px;
}
table.data-t th, table.data-t td {
  border: 1px solid var(--line); padding: 7px 8px; text-align: center;
}
table.data-t th { background: var(--bg-2); font-weight: 800; }
table.data-t tr.hl td { background: var(--primary-soft); }

@media (min-width: 720px) {
  :root { --topbar-h: 60px; }
  body { font-size: 16px; }
  .view { padding-left: 20px; padding-right: 20px; }
}

@media (min-width: 900px) {
  .view { max-width: 920px; }
  .point-detail,
  .drill-wrap {
    max-width: 720px;
    margin-left: auto;
    margin-right: auto;
  }
  .point-card {
    padding: 24px 28px;
  }
  .point-card h2 {
    font-size: 22px;
    line-height: 1.4;
  }
  .steps li {
    font-size: 15.5px;
    line-height: 1.7;
  }
  .flash {
    min-height: 260px;
    padding: 32px 28px;
  }
  .flash-q { font-size: 26px; }
  .flash.flipped .flash-q { font-size: 17px; }
  .tip-box, .mnem-box, .explain { font-size: 14.5px; }
  .hero, .subj-list, .chap-list, .viz-list, .stat-grid, .quick-list {
    max-width: 860px;
  }
}

/* =========================================================
   精致化补丁：按钮 / 标签 / 底栏 / 表格
   ========================================================= */
.btn {
  border-radius: 14px;
  transition: transform .12s ease, box-shadow .16s ease, background .16s ease, border-color .16s ease;
}
.btn.primary {
  box-shadow: 0 4px 14px rgba(13, 148, 136, .28);
}
.btn.primary:hover { box-shadow: 0 6px 18px rgba(13, 148, 136, .32); }
.btn.sm { border-radius: 10px; }

.chip {
  letter-spacing: .1px;
  box-shadow: 0 1px 2px rgba(0,0,0,.04);
}
.chip.star {
  box-shadow: 0 1px 2px rgba(202,138,4,.15);
}
.chip.demo {
  box-shadow: 0 1px 2px rgba(37,99,235,.15);
}
.chip.warn {
  box-shadow: 0 1px 2px rgba(217,119,6,.15);
}

.quick-btn {
  transition: transform .14s ease, box-shadow .16s ease, border-color .16s ease;
}
.quick-btn:hover { border-color: var(--primary); }

.chap-head { transition: background .16s ease; }
.chap-head:hover { background: var(--bg-2); }

.grade-btn {
  border-radius: 18px;
  box-shadow: 0 2px 8px rgba(15,40,30,.05);
}
.grade-btn:hover:not(:disabled) {
  transform: translateY(-1px);
  box-shadow: 0 6px 16px rgba(15,40,30,.08);
}

.metric {
  border-radius: 14px;
  background: linear-gradient(180deg, var(--card) 0%, var(--bg-2) 100%);
}

table.data-t {
  border-radius: 12px;
  overflow: hidden;
  border: 1px solid var(--line);
}
table.data-t th, table.data-t td {
  border: none;
  border-bottom: 1px solid var(--line);
}
table.data-t tr:last-child td { border-bottom: none; }

.stage {
  border-radius: 16px;
  background:
    linear-gradient(180deg, var(--stage-bg) 0%, var(--bg-2) 100%);
}

.tip-box, .mnem-box, .explain {
  border-radius: 0 14px 14px 0;
}

.sec-title {
  color: var(--primary-ink);
  opacity: .75;
}

/* 深色下的点缀 */
[data-theme="dark"] .hero { box-shadow: 0 8px 28px rgba(0,0,0,.25); }
[data-theme="dark"] .subj-card:hover { border-color: var(--primary); }
[data-theme="dark"] .quick-btn:hover { border-color: var(--primary); }
[data-theme="dark"] .viz-card:hover { border-color: var(--primary); }
[data-theme="dark"] .metric {
  background: linear-gradient(180deg, var(--card) 0%, #141a17 100%);
}

/* =========================================================
   v4 大升级：科目区分色 / 桌面侧边栏 / 仪表盘 / 真题 / 教材
   ========================================================= */
:root {
  --c-ds: #0d9488; --c-ds-soft: #e0f5f1;
  --c-co: #7c3aed; --c-co-soft: #f3f0ff;
  --c-os: #2563eb; --c-os-soft: #eff6ff;
  --c-cn: #ea580c; --c-cn-soft: #fff3ea;
  --sidebar-w: 224px;
}
[data-theme="dark"] {
  --c-ds-soft: #12352f; --c-co-soft: #2a2140;
  --c-os-soft: #1a2740; --c-cn-soft: #3a2413;
}
.chip.s-ds { background: var(--c-ds-soft); color: var(--c-ds); }
.chip.s-co { background: var(--c-co-soft); color: var(--c-co); }
.chip.s-os { background: var(--c-os-soft); color: var(--c-os); }
.chip.s-cn { background: var(--c-cn-soft); color: var(--c-cn); }

/* —— 桌面侧边导航 —— */
#sidebar { display: none; }
@media (min-width: 1024px) {
  #sidebar {
    display: flex; flex-direction: column;
    position: fixed; left: 0; top: 0; bottom: 0;
    width: var(--sidebar-w); z-index: 45;
    background: var(--card); border-right: 1px solid var(--line);
    padding: 18px 12px; gap: 2px; overflow-y: auto;
  }
  .side-brand {
    display: flex; align-items: center; gap: 10px;
    padding: 4px 10px 16px; font-weight: 800; font-size: 16px;
  }
  .side-brand .logo-dot {
    width: 30px; height: 30px; border-radius: 9px;
    background: var(--grad); color: #fff;
    display: grid; place-items: center; font-size: 14px;
  }
  .side-group {
    margin: 10px 10px 4px; font-size: 11px; font-weight: 800;
    color: var(--muted); letter-spacing: .8px;
  }
  .side-link {
    display: flex; align-items: center; gap: 10px;
    padding: 9px 12px; border-radius: 11px;
    font-size: 14px; font-weight: 600; color: var(--ink-2);
    text-align: left; width: 100%;
  }
  .side-link svg { width: 19px; height: 19px; flex-shrink: 0; opacity: .8; }
  .side-link:hover { background: var(--bg-2); }
  .side-link.on {
    background: var(--primary-soft); color: var(--primary-ink);
    font-weight: 800;
  }
  /* 顶栏与主区右移 */
  .topbar { left: var(--sidebar-w); width: calc(100% - var(--sidebar-w)); }
  .view {
    margin-left: var(--sidebar-w);
    max-width: none; width: calc(100% - var(--sidebar-w));
    padding-left: 28px; padding-right: 28px;
  }
  .tabbar { display: none !important; }
  .offline-bar { left: calc(var(--sidebar-w) + 12px); right: 12px; bottom: 12px; }
  .toast { bottom: 24px; }
  body { --tabbar-h: 0px; }
}

/* —— 仪表盘：概览条 —— */
.stat-strip { display: grid; grid-template-columns: repeat(4, 1fr); gap: 10px; }
@media (max-width: 560px) { .stat-strip { grid-template-columns: 1fr 1fr; } }
.stat-tile {
  background: var(--card); border: 1px solid var(--line);
  border-radius: var(--radius); box-shadow: var(--shadow);
  padding: 14px 14px 12px; display: grid; gap: 2px;
}
.stat-tile .st-n { font-size: 22px; font-weight: 800; line-height: 1.1; }
.stat-tile .st-l { font-size: 12px; color: var(--muted); }
.stat-tile.accent-due .st-n { color: var(--primary); }
.stat-tile.accent-new .st-n { color: var(--blue); }
.stat-tile.accent-streak .st-n { color: var(--warn); }
.stat-tile.accent-master .st-n { color: var(--ok); }

.mod-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 10px; }
@media (max-width: 560px) { .mod-grid { grid-template-columns: 1fr; } }
.mod-card {
  display: flex; align-items: center; gap: 12px;
  background: var(--card); border: 1px solid var(--line);
  border-radius: var(--radius); box-shadow: var(--shadow);
  padding: 16px; text-align: left; width: 100%;
}
.mod-card:active { transform: scale(.985); }
.mod-ico {
  width: 44px; height: 44px; border-radius: 13px; flex-shrink: 0;
  display: grid; place-items: center; font-size: 20px; color: #fff;
}
.mod-ico.exam { background: linear-gradient(135deg,#f43f5e,#be123c); }
.mod-ico.book { background: linear-gradient(135deg,#0ea5e9,#0369a1); }
.mod-main { flex: 1; min-width: 0; }
.mod-main b { display: block; font-size: 15px; }
.mod-main span { font-size: 12px; color: var(--muted); }

/* —— 真题 —— */
.year-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(150px, 1fr)); gap: 10px; }
.year-card {
  background: var(--card); border: 1px solid var(--line);
  border-radius: var(--radius); box-shadow: var(--shadow);
  padding: 14px; text-align: left; display: grid; gap: 4px;
}
.year-card:active { transform: scale(.97); }
.year-card .y-n { font-size: 19px; font-weight: 800; }
.year-card .y-m { font-size: 12px; color: var(--muted); }
.year-card .y-tags { display: flex; gap: 4px; flex-wrap: wrap; margin-top: 4px; }
.year-card .y-tags .chip { font-size: 10.5px; padding: 2px 7px; }

.exam-filter { display: flex; gap: 6px; flex-wrap: wrap; margin: 4px 0 12px; }
.exam-filter .seg button { padding: 6px 12px; }

.exam-layout { display: grid; gap: 14px; }
@media (min-width: 1024px) {
  .exam-layout { grid-template-columns: minmax(0, 1.05fr) minmax(0, 1fr); align-items: start; }
  .exam-pdf-col { position: sticky; top: calc(var(--topbar-h) + 12px); }
}
.exam-pdf-bar { display: flex; gap: 8px; align-items: center; flex-wrap: wrap; margin-bottom: 8px; }
.exam-pdf-frame {
  width: 100%; height: 72vh; min-height: 480px;
  border: 1px solid var(--line); border-radius: 14px; background: #525659;
}
.ans-quick {
  background: var(--card); border: 1px solid var(--line);
  border-radius: var(--radius-sm); padding: 10px 12px; margin-bottom: 12px;
  font-size: 12.5px; line-height: 1.9; word-break: break-all;
}
.ans-quick b { color: var(--primary-ink); }

.q-sec-title {
  margin: 14px 2px 8px; font-size: 13px; font-weight: 800; color: var(--muted);
  letter-spacing: .5px;
}
.q-list { display: grid; gap: 8px; }
.q-card {
  background: var(--card); border: 1px solid var(--line);
  border-radius: 14px; padding: 13px 14px; box-shadow: var(--shadow);
}
.q-card.hl { outline: 2px solid var(--primary); }
.q-head { display: flex; align-items: center; gap: 6px; flex-wrap: wrap; margin-bottom: 6px; }
.q-no {
  min-width: 24px; height: 22px; padding: 0 7px; border-radius: 7px;
  background: var(--primary-soft); color: var(--primary-ink);
  font-size: 12px; font-weight: 800; display: grid; place-items: center;
}
.q-stem { font-size: 14.5px; line-height: 1.65; }
.q-opts { margin: 8px 0 0; padding: 0; list-style: none; display: grid; gap: 5px; }
.q-opts li {
  display: flex; gap: 8px; font-size: 13.5px;
  padding: 6px 10px; border-radius: 9px; background: var(--bg-2);
}
.q-opts li.ans { background: var(--ok-soft); font-weight: 700; }
.q-opts .opt-k { font-weight: 800; color: var(--muted); }
.q-opts li.ans .opt-k { color: var(--ok); }
.q-ans-row { margin-top: 8px; display: flex; gap: 8px; align-items: center; flex-wrap: wrap; }
.q-ans-badge {
  display: inline-grid; place-items: center; min-width: 30px; height: 24px;
  padding: 0 8px; border-radius: 8px;
  background: var(--ok); color: #fff; font-weight: 800; font-size: 13px;
}
.q-analysis {
  margin-top: 8px; padding: 10px 12px;
  border-left: 3px solid var(--primary); background: var(--primary-soft);
  border-radius: 0 10px 10px 0; font-size: 13px; line-height: 1.65;
  display: none;
}
.q-card.open .q-analysis { display: block; }
.q-toggle { font-size: 12px; color: var(--primary); font-weight: 700; }

/* —— 教材 —— */
.ebook-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 10px; }
@media (max-width: 640px) { .ebook-grid { grid-template-columns: 1fr; } }
.ebook-card {
  background: var(--card); border: 1px solid var(--line);
  border-radius: var(--radius); box-shadow: var(--shadow);
  padding: 16px; text-align: left; display: grid; gap: 6px;
}
.ebook-card:active { transform: scale(.985); }
.ebook-card h3 { margin: 0; font-size: 15px; font-weight: 800; }
.ebook-card .eb-meta { font-size: 12px; color: var(--muted); }
.ebook-card .eb-foot { display: flex; gap: 6px; flex-wrap: wrap; margin-top: 4px; }

.ebook-layout { display: grid; gap: 0; }
@media (min-width: 900px) {
  .ebook-layout { grid-template-columns: 280px minmax(0, 1fr); gap: 14px; align-items: start; }
  .toc-panel { position: sticky; top: calc(var(--topbar-h) + 12px); max-height: calc(100vh - var(--topbar-h) - 24px); }
  .toc-toggle { display: none; }
}
.toc-panel {
  background: var(--card); border: 1px solid var(--line);
  border-radius: 14px; padding: 8px; overflow-y: auto;
  max-height: 46vh;
}
.toc-node { display: grid; gap: 1px; }
.toc-item {
  display: flex; align-items: baseline; gap: 6px; width: 100%;
  padding: 6px 8px; border-radius: 8px; text-align: left; font-size: 13px;
  line-height: 1.4;
}
.toc-item:hover { background: var(--bg-2); }
.toc-item.on { background: var(--primary-soft); color: var(--primary-ink); font-weight: 700; }
.toc-item .toc-t { flex: 1; min-width: 0; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.toc-item .toc-p { font-size: 11px; color: var(--muted); font-variant-numeric: tabular-nums; flex-shrink: 0; }
.toc-l1 .toc-t { font-weight: 700; }
.toc-l2 { padding-left: 18px; font-size: 12.5px; }
.toc-l3 { padding-left: 34px; font-size: 12px; color: var(--ink-2); }
.toc-lx { padding-left: 48px; font-size: 12px; color: var(--muted); }
.ebook-frame {
  width: 100%; height: calc(100vh - var(--topbar-h) - 24px); min-height: 70vh;
  border: 1px solid var(--line); border-radius: 14px; background: #525659;
}
.toc-mask { display: none; }
@media (max-width: 899px) {
  .toc-panel { display: none; }
  .toc-panel.open { display: block; position: fixed; left: 12px; right: 12px; top: 64px; bottom: 12px; z-index: 60; max-height: none; box-shadow: var(--shadow-lg); }
  .toc-mask.show { display: block; position: fixed; inset: 0; z-index: 59; background: rgba(0,0,0,.4); }
  .ebook-frame { height: 72vh; }
}

/* 相关真题 chips 区 */
.exam-chip-row { display: flex; gap: 6px; flex-wrap: wrap; }
.exam-chip {
  display: inline-flex; align-items: center; gap: 4px;
  padding: 4px 10px; border-radius: 999px;
  background: var(--danger-soft); color: #be123c;
  font-size: 12px; font-weight: 700;
}
.exam-chip:hover { filter: brightness(.96); }
[data-theme="dark"] .exam-chip { color: #fda4af; }
.ebook-ref-row { display: flex; gap: 8px; flex-wrap: wrap; }
.ebook-ref {
  display: inline-flex; align-items: center; gap: 6px;
  padding: 6px 12px; border-radius: 10px;
  background: var(--blue-soft); color: var(--blue);
  font-size: 12.5px; font-weight: 700;
}
.ebook-ref:hover { filter: brightness(.96); }

/* =========================================================
   v5 打磨：首页面板 / 离线 PDF.js 阅读器 / 真题做题模式
   ========================================================= */
/* —— 首页：Hero 装饰 —— */
.dash-hero { position: relative; overflow: hidden; }
.dash-blob { position: absolute; border-radius: 50%; filter: blur(2px); opacity: .16; pointer-events: none; }
.dash-blob.b1 { width: 220px; height: 220px; right: -60px; top: -70px; background: radial-gradient(circle, #5eead4, transparent 70%); }
.dash-blob.b2 { width: 140px; height: 140px; left: 34%; bottom: -70px; background: radial-gradient(circle, #a78bfa, transparent 70%); }
.dash-blob.b3 { width: 90px; height: 90px; right: 22%; bottom: 6px; background: radial-gradient(circle, #fb923c, transparent 70%); }
.hero-greet { font-size: 13.5px; font-weight: 700; opacity: .92; margin-bottom: 4px; }
.hero-cta { display: flex; align-items: center; gap: 12px; flex-wrap: wrap; margin-top: 14px; position: relative; z-index: 1; }
.hero-plan { font-size: 12.5px; opacity: .9; }
[data-theme="dark"] .dash-blob { opacity: .10; }

/* —— 首页：统计条 v2 —— */
.stat-tile {
  border-radius: 16px; padding: 12px 14px 12px;
  display: grid; gap: 6px;
  position: relative; overflow: hidden;
  transition: transform .14s ease, box-shadow .16s ease;
}
.stat-tile:hover { transform: translateY(-2px); box-shadow: var(--shadow-lg); }
.stat-tile::before {
  content: ''; position: absolute; left: 0; top: 0; bottom: 0; width: 4px;
  background: var(--line); opacity: .6;
}
.stat-tile.accent-master::before { background: var(--ok); }
.stat-tile.accent-due::before { background: var(--primary); }
.stat-tile.accent-new::before { background: var(--blue); }
.stat-tile.accent-streak::before { background: var(--warn); }
.st-top { display: flex; align-items: center; gap: 6px; }
.st-ico { font-size: 15px; line-height: 1; }
.stat-tile .st-n { font-size: 26px; font-weight: 800; letter-spacing: -.5px; }
.stat-tile .st-l { font-size: 12px; color: var(--muted); }

/* —— 首页：资源卡 v2 —— */
.mod-card { transition: transform .14s ease, box-shadow .16s ease, border-color .16s ease; }
.mod-card:hover { transform: translateY(-2px); box-shadow: var(--shadow-lg); border-color: var(--line); }
.mod-ico { box-shadow: 0 6px 14px rgba(0,0,0,.10); }
.mod-main b { font-size: 16px; }
.mod-main .mod-sub {
  display: block; margin-top: 3px; font-size: 11.5px;
  color: var(--primary); font-weight: 700;
}
.mod-card.exam .mod-sub { color: var(--c-cn); }
.mod-card.book .mod-sub { color: var(--blue); }
.mod-arrow {
  font-size: 18px; color: var(--muted); flex-shrink: 0;
  transition: transform .16s ease;
}
.mod-card:hover .mod-arrow { transform: translateX(3px); color: var(--primary); }

.chip.ok { background: var(--ok-soft); color: var(--ok); }

/* —— 离线 PDF.js 阅读器 —— */
.ebook-pdf-host { width: 100%; height: calc(100vh - var(--topbar-h) - 24px); min-height: 70vh; }
.exam-pdf-host { width: 100%; height: 72vh; min-height: 480px; }
.pdfv {
  display: flex; flex-direction: column; height: 100%;
  border: 1px solid var(--line); border-radius: 14px; overflow: hidden;
  background: var(--card);
}
.pdfv-bar {
  display: flex; align-items: center; gap: 8px;
  padding: 7px 10px; border-bottom: 1px solid var(--line);
  background: var(--bg-2); flex-shrink: 0;
}
.pdfv-btn {
  min-width: 32px; height: 30px; padding: 0 6px;
  border-radius: 8px; border: 1px solid var(--line);
  background: var(--card); color: var(--ink-2);
  font-size: 16px; line-height: 1; cursor: pointer;
  display: grid; place-items: center;
}
.pdfv-btn:hover { border-color: var(--primary); color: var(--primary); }
.pdfv-page, .pdfv-scale { font-size: 12px; color: var(--muted); font-variant-numeric: tabular-nums; white-space: nowrap; }
.pdfv-gap { flex: 1; }
.pdfv-stage {
  flex: 1; overflow: auto; position: relative;
  background: #525659; padding: 12px;
  display: flex; align-items: flex-start; justify-content: center;
}
.pdfv-stage canvas { background: #fff; box-shadow: 0 2px 12px rgba(0,0,0,.35); }
.pdfv-msg {
  position: absolute; left: 0; right: 0; top: 40px;
  display: flex; justify-content: center; pointer-events: none;
  font-size: 13px; color: #e5e7eb;
}
[data-theme="dark"] .pdfv-bar { background: #1a221e; }
[data-theme="dark"] .pdfv-stage { background: #1c1f1d; }

/* —— 真题：做题模式 —— */
.exam-ctrl { display: flex; justify-content: space-between; align-items: center; margin: 2px 0 10px; flex-wrap: wrap; gap: 8px; }
.exam-mode { display: inline-flex; }
.exam-mode button { padding: 6px 14px; }
.exam-score {
  display: flex; align-items: center; gap: 10px; flex-wrap: wrap;
  background: var(--card); border: 1px solid var(--line);
  border-radius: 12px; padding: 8px 12px; margin-bottom: 10px;
}
.score-info { font-size: 12.5px; font-weight: 700; color: var(--ink-2); white-space: nowrap; }
.score-bar { flex: 1; min-width: 90px; height: 8px; border-radius: 99px; background: var(--bg-2); overflow: hidden; }
.score-fill { height: 100%; width: 0; border-radius: 99px; background: var(--grad); transition: width .3s ease; }

.q-imgs { margin: 8px 0 2px; display: flex; gap: 10px; flex-wrap: wrap; }
.q-imgs img {
  max-width: 100%; max-height: 320px;
  border: 1px solid var(--line); border-radius: 10px;
  background: #fff; object-fit: contain;
}
[data-theme="dark"] .q-imgs img { background: #fff; }

.q-goto-pdf {
  margin-left: auto; font-size: 11.5px; font-weight: 700;
  color: var(--blue); background: var(--blue-soft);
  border-radius: 8px; padding: 3px 8px; border: none; cursor: pointer;
}
.q-goto-pdf:hover { filter: brightness(.95); }

/* 做题选项按钮 */
.q-opts .q-opt {
  display: flex; gap: 8px; align-items: flex-start;
  width: 100%; text-align: left;
  font-size: 13.5px; line-height: 1.55; font-family: var(--font);
  padding: 8px 10px; border-radius: 10px;
  background: var(--bg-2); border: 1.5px solid transparent;
  cursor: pointer; color: var(--ink); transition: border-color .12s ease, background .12s ease;
}
.q-opts .q-opt:hover:not(:disabled) { border-color: var(--primary); background: var(--primary-soft); }
.q-opts .q-opt .opt-k { font-weight: 800; color: var(--muted); flex-shrink: 0; }
.q-opts .q-opt.right { background: var(--ok-soft); border-color: var(--ok); }
.q-opts .q-opt.right .opt-k { color: var(--ok); }
.q-opts .q-opt.wrong { background: var(--danger-soft); border-color: var(--danger); }
.q-opts .q-opt.wrong .opt-k { color: var(--danger); }
.q-opts .q-opt:disabled { cursor: default; }

.q-feedback {
  margin-top: 8px; gap: 10px; align-items: center; flex-wrap: wrap;
  font-size: 13px; font-weight: 800;
}
.fb-ok { color: var(--ok); }
.fb-no { color: var(--danger); }
.q-feedback .q-toggle { font-weight: 700; }

.q-analysis.open { display: block; }

.exam-pdf-pos { font-size: 12px; color: var(--muted); font-variant-numeric: tabular-nums; }
.exam-pdf-toggle { display: none; }
@media (max-width: 1023px) {
  .exam-pdf-col.collapsible { display: none; }
  .exam-pdf-col.collapsible.open { display: block; }
  .exam-pdf-toggle { display: inline-flex; margin-top: 12px; }
  .exam-pdf-host { height: 70vh; }
}
@media (min-width: 1024px) {
  .exam-pdf-col { position: sticky; top: calc(var(--topbar-h) + 12px); }
}

/* 教材目录树滚动条 */
.toc-panel::-webkit-scrollbar { width: 6px; }
.toc-panel::-webkit-scrollbar-thumb { background: var(--line); border-radius: 99px; }
.pdfv-stage::-webkit-scrollbar { width: 8px; height: 8px; }
.pdfv-stage::-webkit-scrollbar-thumb { background: rgba(255,255,255,.25); border-radius: 99px; }

/* =========================================================
   v6 布局：全宽仪表盘 / PDF 抽屉 / 沉浸阅读器 / 宽屏网格
   ========================================================= */
/* 宽屏放宽主容器 */
@media (min-width: 1280px) { .view { max-width: 1440px; } }
@media (min-width: 900px) {
  .hero, .subj-list, .chap-list, .viz-list, .stat-grid, .quick-list { max-width: none; }
}

/* —— 首页仪表盘 v6 —— */
.dash-hero { display: flex; gap: 16px; align-items: stretch; }
.dash-hero .ring { width: 86px; height: 86px; }
.dash-hero .ring-in { width: 70px; height: 70px; }
@media (max-width: 1100px) { .dash-hero { flex-direction: column; } }
.hero-title { font-size: 20px; font-weight: 800; margin: 4px 0 10px; letter-spacing: .3px; }
.hero-left { flex: 1; min-width: 0; }
.hero-stats { display: flex; align-items: center; gap: 20px; flex-wrap: wrap; position: relative; z-index: 1; }
.hero-nums { display: grid; grid-template-columns: repeat(3, auto); gap: 4px 26px; }
.hn { display: grid; gap: 0; }
.hn b { font-size: 26px; font-weight: 800; line-height: 1.15; }
.hn span { font-size: 12px; opacity: .82; }

.hero-tasks {
  flex: 0 0 390px;
  background: rgba(255,255,255,.10);
  border: 1px solid rgba(255,255,255,.20);
  border-radius: 18px; padding: 12px;
  display: grid; gap: 9px;
  backdrop-filter: blur(6px);
  position: relative; z-index: 1;
}
.task-row {
  display: flex; align-items: center; gap: 10px;
  background: rgba(255,255,255,.95); color: var(--ink);
  border-radius: 12px; padding: 9px 12px;
}
.task-ico { font-size: 19px; line-height: 1; }
.task-main { flex: 1; min-width: 0; display: grid; gap: 1px; }
.task-l { font-size: 10.5px; color: var(--muted); font-weight: 800; }
.task-n b { font-size: 16px; }
.task-hint { font-size: 10.5px; color: var(--muted); }
.task-go { min-height: 32px; padding: 0 12px; border-radius: 9px; font-size: 12.5px; }
[data-theme="dark"] .task-row { background: #1a221e; }
[data-theme="dark"] .hero-tasks { background: rgba(0,0,0,.16); }

.dash-body { display: grid; grid-template-columns: minmax(0, 1fr) 320px; gap: 14px; margin-top: 14px; align-items: start; }
@media (max-width: 1100px) {
  .dash-body { grid-template-columns: 1fr; }
  .hero-tasks { flex-basis: 100%; }
  .dash-side { position: static; }
}
.dash-main { display: grid; gap: 2px; min-width: 0; }
.dash-side { display: grid; gap: 12px; position: sticky; top: calc(var(--topbar-h) + 12px); }

.side-card { background: var(--card); border: 1px solid var(--line); border-radius: var(--radius); box-shadow: var(--shadow); padding: 14px 16px; }
.side-card-head { display: flex; align-items: baseline; justify-content: space-between; margin-bottom: 10px; }
.side-card-head b { font-size: 14px; }
.side-note { font-size: 11.5px; color: var(--muted); }

.heat-row { display: grid; grid-template-columns: repeat(7, 1fr); gap: 6px; }
.heat-cell { display: grid; justify-items: center; gap: 3px; padding: 7px 2px; border-radius: 10px; background: var(--bg-2); }
.heat-cell i { font-style: normal; width: 26px; height: 26px; border-radius: 8px; display: grid; place-items: center; background: var(--card); border: 1px solid var(--line); font-size: 11px; font-weight: 800; color: var(--muted); }
.heat-cell.on i { background: var(--primary-soft); color: var(--primary-ink); border-color: transparent; }
.heat-cell.on.hot i { background: var(--grad); color: #fff; }
.heat-cell span { font-size: 10px; color: var(--muted); }
.heat-foot { margin-top: 9px; font-size: 12px; color: var(--muted); }

.prog-row { display: grid; grid-template-columns: 76px 1fr 38px; align-items: center; gap: 8px; margin: 7px 0; }
.prog-name { font-size: 12.5px; font-weight: 700; }
.prog-pct { font-size: 12px; font-weight: 800; color: var(--primary); text-align: right; }
.tip-p { margin: 0; font-size: 13px; line-height: 1.65; color: var(--ink-2); }

/* 宽屏：四科目一行 */
@media (min-width: 1400px) {
  .subj-list { grid-template-columns: repeat(4, 1fr); }
}

/* —— 真题：PDF 抽屉 —— */
.pdf-mask { position: fixed; inset: 0; background: rgba(15,25,20,.35); opacity: 0; pointer-events: none; transition: opacity .22s ease; z-index: 70; }
.pdf-mask.show { opacity: 1; pointer-events: auto; }
.pdf-drawer {
  position: fixed; top: 0; right: 0; bottom: 0; z-index: 71;
  width: min(620px, 94vw);
  background: var(--bg);
  border-left: 1px solid var(--line);
  box-shadow: -14px 0 44px rgba(0,0,0,.18);
  display: flex; flex-direction: column;
  transform: translateX(103%); transition: transform .26s cubic-bezier(.22,1,.36,1);
}
.pdf-drawer.open { transform: none; }
.drawer-top { display: flex; align-items: center; gap: 12px; padding: 10px 14px; background: var(--card); border-bottom: 1px solid var(--line); flex-shrink: 0; }
.drawer-top .icon-btn { margin-left: auto; }
.pdf-drawer .exam-pdf-host { height: auto; flex: 1; min-height: 0; border: none; border-radius: 0; }
.pdf-drawer .pdfv { border: none; border-radius: 0; }
.exam-fab {
  position: fixed; right: 22px; bottom: 24px; z-index: 65;
  min-height: 46px; padding: 0 18px; border-radius: 999px;
  background: var(--grad); color: #fff; font-weight: 800; font-size: 14px;
  box-shadow: 0 8px 24px rgba(13,148,136,.4);
  display: inline-flex; align-items: center; gap: 6px;
  transition: transform .14s ease, box-shadow .16s ease;
}
.exam-fab:hover { transform: translateY(-2px); box-shadow: 0 10px 28px rgba(13,148,136,.5); }
@media (min-width: 1024px) { .exam-fab { right: calc(var(--sidebar-w) + 26px); } }
[data-theme="dark"] .pdf-drawer { background: #141a17; }

/* 题目列最大阅读宽度（避免过宽） */
@media (min-width: 1100px) { .q-list { max-width: 1080px; } }

/* —— 沉浸式教材阅读器 —— */
.ebook-reader { display: flex; gap: 12px; align-items: flex-start; }
.ebook-reader .toc-toggle { flex-shrink: 0; min-height: 38px; }
.ebook-reader .toc-panel {
  width: 264px; flex-shrink: 0;
  position: sticky; top: calc(var(--topbar-h) + 12px);
  max-height: calc(100vh - var(--topbar-h) - 24px);
}
.ebook-reader .ebook-pdf-host { flex: 1; min-width: 0; height: calc(100vh - var(--topbar-h) - 24px); min-height: 60vh; }
.ebook-reader.toc-hidden .toc-panel { display: none; }
@media (max-width: 899px) {
  .ebook-reader { flex-direction: column; }
  .ebook-reader .toc-panel {
    position: fixed; left: 12px; right: 12px; top: 64px; bottom: 12px;
    z-index: 60; width: auto; max-height: none;
    display: none;
  }
  .ebook-reader .toc-panel.open { display: block; }
  .ebook-reader .ebook-pdf-host { height: calc(100vh - var(--topbar-h) - 84px); min-height: 60vh; }
}

/* —— 可视化：宽屏自适应网格 —— */
@media (min-width: 1000px) {
  .viz-list { grid-template-columns: repeat(auto-fill, minmax(320px, 1fr)); }
}


/* ===== 授权门（卡密 / 试用） ===== */
.gate-mode #sidebar { display: none !important; }
@media (min-width: 1024px) {
  .gate-mode .topbar { left: 0; width: 100%; }
  .gate-mode .view { margin-left: 0; width: 100%; max-width: none; }
  .gate-mode .offline-bar { left: 12px; }
}
.gate-card {
  min-height: calc(100vh - var(--topbar-h) - 40px);
  display: grid; place-items: center; padding: 28px 16px 60px;
}
.gate-inner {
  width: 100%; max-width: 430px; background: var(--card);
  border: 1px solid var(--line); border-radius: 24px; box-shadow: var(--shadow-lg);
  padding: 36px 30px; text-align: center;
}
.gate-logo {
  width: 66px; height: 66px; margin: 0 auto 14px; border-radius: 18px;
  background: var(--grad); color: #fff; display: grid; place-items: center;
  font-size: 26px; font-weight: 900; box-shadow: 0 8px 22px rgba(13,148,136,.35);
}
.gate-title { font-size: 20px; font-weight: 800; }
.gate-sub { font-size: 12px; color: var(--muted); margin: 4px 0 22px; }
.gate-keybox { display: flex; flex-direction: column; gap: 8px; }
.gate-input {
  width: 100%; padding: 12px 14px; border: 1.5px solid var(--line);
  border-radius: 12px; font: inherit; font-family: var(--mono); font-size: 14px;
  letter-spacing: .5px; background: var(--card); color: var(--ink); text-align: center;
}
.gate-input:focus { outline: none; border-color: var(--primary); box-shadow: 0 0 0 3px var(--primary-soft); }
.gate-btn { width: 100%; padding: 12px; border-radius: 12px; font-size: 15px; }
.gate-msg { font-size: 13px; min-height: 18px; color: var(--danger); }
.gate-or { margin: 16px 0; color: var(--muted); font-size: 12px; display: flex; align-items: center; gap: 10px; }
.gate-or::before, .gate-or::after { content: ''; flex: 1; height: 1px; background: var(--line); }
.gate-trial-btn {
  width: 100%; padding: 12px; border-radius: 12px;
  border: 1.5px dashed var(--primary); background: var(--primary-soft);
  color: var(--primary-ink); font-weight: 700; transition: all .15s;
}
.gate-trial-btn:hover { background: var(--primary); color: #fff; }
.gate-tip { margin-top: 16px; font-size: 12px; color: var(--muted); }
.gate-reason {
  margin: 0 0 14px; padding: 10px 12px; border-radius: 10px;
  background: var(--warn-soft); color: var(--warn); font-size: 13px; font-weight: 600;
}
.gate-counting {
  max-width: 430px; margin: 0 auto 14px; background: var(--primary-soft);
  border: 1px solid var(--primary); color: var(--primary-ink); border-radius: 12px;
  padding: 10px 14px; text-align: center; font-size: 14px; font-weight: 600;
}
.gate-counting b { font-family: var(--mono); font-size: 16px; }
/* 试用倒计时：左上角小悬浮胶囊 */
#gate-bar {
  position: fixed; top: calc(var(--topbar-h) + 10px); left: calc(var(--sidebar-w, 220px) + 16px); z-index: 99;
  display: flex; align-items: center; gap: 8px; cursor: move; user-select: none; touch-action: none;
  will-change: left, top;
  background: rgba(15,118,110,.92); color: #fff;
  font-size: 12px; padding: 6px 12px; border-radius: 999px;
  box-shadow: 0 4px 16px rgba(15,118,110,.35);
  backdrop-filter: blur(6px);
}
#gate-bar b { font-family: var(--mono); font-size: 13px; letter-spacing: 1px; }
#gate-bar .btn {
  background: rgba(255,255,255,.18); border: 1px solid rgba(255,255,255,.45);
  color: #fff; font-weight: 600; padding: 2px 10px; border-radius: 999px; font-size: 12px;
}
@media (max-width: 1023px) { #gate-bar { left: 12px; } }
.gate-mode #gate-bar { left: 12px !important; }