/**
 * L15 · 视觉设计 v3 — 清爽编辑风 + 词汇卡片
 */
:root {
  --l15-bg-1: #eef2ff;
  --l15-bg-2: #faf5ff;
  --l15-bg-3: #f0fdfa;
  --l15-ink: #1e1b4b;
  --l15-muted: #64748b;
  --l15-accent: #6366f1;
  --l15-accent-2: #8b5cf6;
  --l15-accent-ink: #4338ca;
  --l15-card: #ffffff;
  --l15-border: rgba(99, 102, 241, 0.14);
  --l15-shadow: 0 10px 40px rgba(67, 56, 202, 0.08);
  --l15-radius: 16px;
  --l15-font: "Segoe UI", system-ui, "PingFang SC", "Microsoft YaHei", sans-serif;
  --l15-serif: "Georgia", "Songti SC", "SimSun", serif;
  --cat-wf: #6366f1;
  --cat-vp: #0ea5e9;
  --cat-an: #14b8a6;
  --cat-col: #f59e0b;
  --cat-idiom: #ec4899;
  --cat-poly: #ef4444;
  --cat-chart: #8b5cf6;
  --cat-t2: #3b82f6;
  --cat-t3: #db2777;
  --cat-pred: #64748b;
}

html, body {
  font-family: var(--l15-font) !important;
  background:
    radial-gradient(ellipse 80% 60% at 10% 0%, var(--l15-bg-1), transparent 55%),
    radial-gradient(ellipse 70% 50% at 90% 10%, var(--l15-bg-2), transparent 50%),
    radial-gradient(ellipse 60% 40% at 50% 100%, var(--l15-bg-3), transparent 45%),
    #f8fafc !important;
  color: var(--l15-ink) !important;
}

#l15-book.book {
  background: var(--l15-card) !important;
  border: 1px solid var(--l15-border) !important;
  border-radius: 20px !important;
  box-shadow: var(--l15-shadow) !important;
}

#l15-book.book::before { display: none !important; }

#l15-book .top-bar {
  margin: 12px 14px 0 !important;
  padding: 10px 16px !important;
  border: 1px solid var(--l15-border) !important;
  border-radius: 14px !important;
  background: linear-gradient(135deg, #fff 0%, #f5f3ff 100%) !important;
  box-shadow: 0 2px 12px rgba(99, 102, 241, 0.06);
}

#l15-book .top-bar strong {
  color: var(--l15-accent-ink) !important;
  letter-spacing: 0.02em;
}

.l15-index-link, .l15-index-link:visited {
  display: inline-flex;
  align-items: center;
  padding: 0.35rem 0.85rem;
  border-radius: 999px;
  background: linear-gradient(135deg, var(--l15-accent), var(--l15-accent-2));
  color: #fff !important;
  font-weight: 700;
  font-size: 0.82rem;
  text-decoration: none;
  box-shadow: 0 4px 14px rgba(99, 102, 241, 0.25);
}

#l15-book .page-head {
  border-bottom: 1px solid var(--l15-border) !important;
  padding-bottom: 0.5rem !important;
}

#l15-book .page-kicker {
  color: var(--l15-muted) !important;
  font-weight: 700;
  background: #eef2ff;
  padding: 0.15rem 0.55rem;
  border-radius: 999px;
}

#l15-book .page-title {
  font-family: var(--l15-serif) !important;
  color: var(--l15-ink) !important;
  font-weight: 800 !important;
}

#l15-book .panel {
  border: 1px solid var(--l15-border) !important;
  border-radius: var(--l15-radius) !important;
  background: #fff !important;
  box-shadow: 0 2px 16px rgba(15, 23, 42, 0.04) !important;
}

#l15-book .zh-hint {
  color: var(--l15-muted) !important;
  font-weight: 600 !important;
  line-height: 1.6;
  padding: 0.55rem 0.75rem;
  background: #f8fafc;
  border-radius: 10px;
  border-left: 3px solid var(--l15-accent);
}

#l15-book .rule-table th {
  background: #eef2ff !important;
  color: var(--l15-accent-ink);
  font-weight: 700;
}

#l15-book .rule-table td { border-color: var(--l15-border) !important; }

#l15-book .panel-lead { font-weight: 700; line-height: 1.55; }
#l15-book .teacher-script {
  margin-top: 0.65rem;
  padding: 0.55rem 0.75rem;
  border-radius: 10px;
  background: linear-gradient(90deg, #eef2ff, #faf5ff);
  font-weight: 700;
  color: var(--l15-accent-ink);
}

.vocab-card {
  position: relative;
  padding: 0.85rem 1rem 0.85rem 1.1rem;
  margin-bottom: 0.65rem;
  border-radius: 14px;
  background: #fff;
  border: 1px solid var(--l15-border);
  box-shadow: 0 2px 10px rgba(15, 23, 42, 0.04);
  transition: box-shadow 0.2s, transform 0.15s;
}
.vocab-card:hover {
  box-shadow: 0 8px 24px rgba(99, 102, 241, 0.1);
  transform: translateY(-1px);
}
.vocab-card::before {
  content: "";
  position: absolute;
  left: 0;
  top: 10px;
  bottom: 10px;
  width: 4px;
  border-radius: 4px;
  background: var(--cat-accent, var(--l15-accent));
}
.vocab-card[data-cat="word-form"] { --cat-accent: var(--cat-wf); }
.vocab-card[data-cat="verb-phrase"] { --cat-accent: var(--cat-vp); }
.vocab-card[data-cat="adj-noun-phrase"] { --cat-accent: var(--cat-an); }
.vocab-card[data-cat="collocation"] { --cat-accent: var(--cat-col); }
.vocab-card[data-cat="idiom"] { --cat-accent: var(--cat-idiom); }
.vocab-card[data-cat="polysemy"] { --cat-accent: var(--cat-poly); }
.vocab-card[data-cat="chart"] { --cat-accent: var(--cat-chart); }
.vocab-card[data-cat="tier2"] { --cat-accent: var(--cat-t2); }
.vocab-card[data-cat="tier3"] { --cat-accent: var(--cat-t3); }
.vocab-card[data-cat="predict"] { --cat-accent: var(--cat-pred); }

.vocab-card-head {
  display: flex;
  flex-wrap: wrap;
  align-items: flex-start;
  justify-content: space-between;
  gap: 0.35rem 0.5rem;
  margin-bottom: 0.45rem;
}
.vocab-card-en {
  font-size: 1.02rem;
  font-weight: 800;
  color: var(--l15-ink);
  line-height: 1.4;
  flex: 1 1 auto;
}
.vocab-card-zh {
  font-size: 0.88rem;
  font-weight: 600;
  color: var(--l15-muted);
  margin-bottom: 0.5rem;
}
.vocab-card-badges {
  display: flex;
  flex-wrap: wrap;
  gap: 0.3rem;
  align-items: center;
}
.vocab-badge {
  font-size: 0.68rem;
  font-weight: 800;
  padding: 0.12rem 0.45rem;
  border-radius: 999px;
  letter-spacing: 0.02em;
}
.vocab-badge.tier2 { background: #dbeafe; color: #1d4ed8; }
.vocab-badge.tier3 { background: #fce7f3; color: #be185d; }
.vocab-badge.year { background: #f1f5f9; color: #475569; }
.vocab-badge.cat {
  background: #eef2ff;
  color: var(--l15-accent-ink);
}

.vocab-example {
  margin-top: 0.45rem;
  padding: 0.6rem 0.75rem;
  border-radius: 10px;
  background: linear-gradient(180deg, #f8fafc 0%, #f1f5f9 100%);
  border: 1px solid rgba(148, 163, 184, 0.2);
}
.vocab-example-label {
  font-size: 0.68rem;
  font-weight: 800;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  color: var(--l15-accent);
  margin-bottom: 0.25rem;
}
.vocab-example-en {
  font-size: 0.9rem;
  font-weight: 700;
  color: #334155;
  line-height: 1.55;
  margin: 0 0 0.3rem;
}
.vocab-example-zh {
  font-size: 0.82rem;
  color: #64748b;
  line-height: 1.5;
  margin: 0;
}
.vocab-ctx {
  margin-top: 0.4rem;
  font-size: 0.72rem;
  font-weight: 700;
  color: #94a3b8;
  display: flex;
  align-items: center;
  gap: 0.35rem;
}
.vocab-ctx::before {
  content: "📍";
  font-size: 0.75rem;
}

.tts-btn {
  flex-shrink: 0;
  border: none;
  background: linear-gradient(135deg, #eef2ff, #e0e7ff);
  color: var(--l15-accent-ink);
  border-radius: 999px;
  padding: 0.25rem 0.55rem;
  font-size: 0.78rem;
  font-weight: 800;
  cursor: pointer;
  box-shadow: 0 2px 6px rgba(99, 102, 241, 0.15);
}
.tts-btn:hover { filter: brightness(1.05); }

.vb-toolbar {
  padding: 0.5rem;
  background: #f8fafc;
  border-radius: 12px;
  border: 1px solid var(--l15-border);
  margin-bottom: 0.65rem;
}
.vb-search {
  border: 1px solid var(--l15-border) !important;
  border-radius: 10px !important;
  padding: 0.5rem 0.75rem !important;
  background: #fff !important;
  font-size: 0.9rem !important;
}
.vb-search:focus {
  outline: 2px solid rgba(99, 102, 241, 0.35);
  border-color: var(--l15-accent) !important;
}
.vb-meta {
  font-size: 0.84rem;
  color: var(--l15-muted);
  padding: 0.35rem 0.15rem;
}
.vb-meta strong { color: var(--l15-accent-ink); }
.vb-tab {
  border: 1px solid var(--l15-border) !important;
  background: #fff !important;
  border-radius: 999px !important;
  padding: 0.3rem 0.7rem !important;
  font-weight: 700 !important;
  font-size: 0.76rem !important;
  transition: all 0.15s;
}
.vb-tab.active {
  background: linear-gradient(135deg, var(--l15-accent), var(--l15-accent-2)) !important;
  color: #fff !important;
  border-color: transparent !important;
  box-shadow: 0 4px 12px rgba(99, 102, 241, 0.25);
}
.vb-list {
  max-height: min(56vh, 480px) !important;
  padding-right: 0.35rem;
}
.vb-list::-webkit-scrollbar { width: 6px; }
.vb-list::-webkit-scrollbar-thumb {
  background: #c7d2fe;
  border-radius: 999px;
}
.vb-pager button {
  background: #fff !important;
  border: 1px solid var(--l15-border) !important;
  border-radius: 10px !important;
  font-weight: 700 !important;
  color: var(--l15-accent-ink) !important;
}
.vb-pager button:not(:disabled):hover {
  background: #eef2ff !important;
}

.bank-year-grid { gap: 0.65rem !important; }
.bank-year-card {
  border: 1px solid var(--l15-border) !important;
  border-radius: 12px !important;
  background: linear-gradient(180deg, #fff, #f8fafc) !important;
  box-shadow: 0 2px 8px rgba(15, 23, 42, 0.04);
}
.bank-year-card h4 {
  color: var(--l15-accent-ink) !important;
  font-family: var(--l15-serif);
}

.stats-strip {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(100px, 1fr));
  gap: 0.45rem;
  margin-bottom: 0.75rem;
}
.stat-pill {
  text-align: center;
  padding: 0.45rem 0.35rem;
  border-radius: 12px;
  background: #fff;
  border: 1px solid var(--l15-border);
}
.stat-pill strong {
  display: block;
  font-size: 1.1rem;
  color: var(--l15-accent-ink);
}
.stat-pill span {
  font-size: 0.68rem;
  color: var(--l15-muted);
  font-weight: 700;
}

.quiz-opt {
  border: 1px solid var(--l15-border) !important;
  border-radius: 12px !important;
  padding: 0.65rem 0.85rem !important;
  font-weight: 600 !important;
  transition: all 0.15s;
}
.quiz-opt:hover { background: #f8fafc !important; }
.quiz-opt.correct {
  border-color: #10b981 !important;
  background: #ecfdf5 !important;
}
.quiz-opt.wrong {
  border-color: #ef4444 !important;
  background: #fef2f2 !important;
}

.vocab-chip {
  border: 1px solid var(--l15-border) !important;
  border-radius: 12px !important;
  box-shadow: 0 1px 4px rgba(15, 23, 42, 0.04);
}
.phrase-block {
  border-left: 4px solid var(--l15-accent) !important;
  border-radius: 0 12px 12px 0 !important;
  background: #f8fafc !important;
}