/* ==========================================================================
   《中药学》第十一版 双语考试复习与 Active Recall 学习平台
   Styles: Modern TCM Medical UI with Light/Dark Themes & Active Recall Modes
   ========================================================================== */

:root {
  --primary: #8C1D18; /* 朱砂漆红 Imperial Cinnabar Lacquer Red */
  --primary-dark: #66100D;
  --primary-light: #F7EBEA;
  --primary-text: #8C1D18;
  --accent-gold: #C5A059; /* 鎏金/古铜 Antique Bronze Gold */
  --accent-gold-dark: #9A7730;
  --accent-gold-light: #FAF4E6;
  --accent-jade: #246B56; /* 翡翠碧玉 Imperial Jade */
  --accent-jade-light: #E8F5F0;
  --danger: #B91C1C;
  --danger-light: #FEE2E2;
  --danger-text: #991B1B;
  --success: #15803D;
  --success-light: #DCFCE7;
  --bg-main: #FAF6EE; /* 仿古宣纸色 Fine Xuan Paper Parchment */
  --bg-card: #FFFDF9;
  --bg-elevated: #FFFFFF;
  --bg-sidebar: #F4EFE6;
  --text-main: #1C1917; /* 徽墨石 Deep Stone Ink */
  --text-muted: #57534E;
  --text-light: #8C8275;
  --border-color: #E6DCCB;
  --border-hover: #C5A059;
  --shadow-sm: 0 1px 3px 0 rgba(70, 50, 30, 0.06);
  --shadow-md: 0 4px 8px -1px rgba(70, 50, 30, 0.08), 0 2px 4px -2px rgba(70, 50, 30, 0.06);
  --shadow-lg: 0 10px 20px -3px rgba(70, 50, 30, 0.12), 0 4px 6px -4px rgba(70, 50, 30, 0.06);
  --radius-sm: 6px;
  --radius-md: 10px;
  --font-sans: -apple-system, BlinkMacSystemFont, "SF Pro Text", "SF Pro Display", "SF Pro Icons", "Sukhumvit Set", "Prompt", "Thonburi", "Inter", "Helvetica Neue", Helvetica, Arial, sans-serif;
  --font-serif-zh: "Noto Serif SC", "Source Han Serif SC", "Songti SC", "SimSun", "STSong", serif;
  --font-mono: ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, monospace;
}

[data-theme="dark"] {
  --primary: #D14942;
  --primary-dark: #A91E18;
  --primary-light: #381614;
  --primary-text: #F87171;
  --accent-gold: #E5C158;
  --accent-gold-dark: #C5A059;
  --accent-gold-light: #33270F;
  --accent-jade: #34D399;
  --accent-jade-light: #0A3A2A;
  --danger: #F87171;
  --danger-light: #450A0A;
  --danger-text: #FCA5A5;
  --success: #34D399;
  --success-light: #064E3B;
  --bg-main: #13110F; /* 墨夜紫禁 Dark Imperial Court */
  --bg-card: #1D1A17;
  --bg-elevated: #282420;
  --bg-sidebar: #171513;
  --text-main: #F5EFE6;
  --text-muted: #B5AAA0;
  --text-light: #7E746A;
  --border-color: #38322B;
  --border-hover: #E5C158;
  --shadow-sm: 0 1px 3px 0 rgba(0, 0, 0, 0.6);
  --shadow-md: 0 4px 8px -1px rgba(0, 0, 0, 0.5);
  --shadow-lg: 0 10px 20px -3px rgba(0, 0, 0, 0.6);
}

/* Reset & Base */
* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
  -webkit-tap-highlight-color: transparent;
}

body {
  font-family: var(--font-sans);
  background-color: var(--bg-main);
  color: var(--text-main);
  line-height: 1.6;
  transition: background-color 0.25s ease, color 0.25s ease;
  overflow-x: hidden;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  text-rendering: optimizeLegibility;
}

/* Layout */
.app-container {
  display: flex;
  min-height: 100vh;
}

/* Sidebar */
.sidebar {
  width: 280px;
  background: var(--bg-sidebar);
  border-right: 1px solid var(--border-color);
  display: flex;
  flex-direction: column;
  flex-shrink: 0;
  position: sticky;
  top: 0;
  height: 100vh;
  z-index: 40;
  transition: transform 0.3s ease, background-color 0.25s ease;
}

.sidebar-brand {
  padding: 16px 18px;
  border-bottom: 1px solid var(--border-color);
  display: flex;
  align-items: center;
  gap: 12px;
}

.brand-logo-img {
  width: 48px;
  height: 48px;
  border-radius: 50%;
  object-fit: cover;
  background: #ffffff;
  border: 2px solid var(--accent-gold);
  box-shadow: 0 3px 10px rgba(0, 0, 0, 0.12);
  flex-shrink: 0;
  transition: transform 0.25s ease, box-shadow 0.25s ease;
}

.brand-logo-img:hover {
  transform: scale(1.08) rotate(3deg);
  box-shadow: 0 4px 14px rgba(184, 134, 11, 0.3);
}

.brand-text-block {
  flex: 1;
  min-width: 0;
}

.brand-badge {
  display: inline-block;
  font-size: 0.68rem;
  font-weight: 600;
  text-transform: uppercase;
  background: var(--primary-light);
  color: var(--primary-text);
  padding: 2px 7px;
  border-radius: 4px;
  margin-bottom: 4px;
  letter-spacing: 0.4px;
  white-space: nowrap;
}

.brand-title {
  font-family: var(--font-serif-zh);
  font-size: 1.32rem;
  font-weight: 800;
  color: var(--primary-dark);
  line-height: 1.2;
  letter-spacing: 0.4px;
}

.brand-sub {
  font-size: 0.76rem;
  color: var(--text-muted);
  margin-top: 3px;
  line-height: 1.25;
}

.nav-menu {
  padding: 16px 12px;
  flex: 1;
  overflow-y: auto;
  display: flex;
  flex-direction: column;
  gap: 4px;
}

.nav-item {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 12px 16px;
  border-radius: var(--radius-md);
  color: var(--text-muted);
  text-decoration: none;
  font-weight: 600;
  font-size: 0.92rem;
  cursor: pointer;
  transition: all 0.2s ease;
  border: none;
  background: none;
  width: 100%;
  text-align: left;
}

.nav-item:hover {
  background: rgba(13, 148, 136, 0.08);
  color: var(--primary);
}

.nav-item.active {
  background: var(--primary);
  color: #ffffff;
  box-shadow: 0 4px 12px rgba(13, 148, 136, 0.25);
}

.nav-item .icon {
  font-size: 1.2rem;
  width: 24px;
  display: flex;
  justify-content: center;
}

.sidebar-footer {
  padding: 16px 20px;
  border-top: 1px solid var(--border-color);
  font-size: 0.8rem;
  color: var(--text-muted);
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.theme-toggle-btn {
  display: flex;
  align-items: center;
  justify-content: space-between;
  width: 100%;
  padding: 8px 12px;
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-sm);
  color: var(--text-main);
  font-size: 0.85rem;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.2s;
}

.theme-toggle-btn:hover {
  border-color: var(--primary);
}

/* Main Content Area */
.main-content {
  flex: 1;
  display: flex;
  flex-direction: column;
  min-width: 0;
  background: var(--bg-main);
}

/* Header */
.top-header {
  position: sticky;
  top: 0;
  z-index: 30;
  background: rgba(248, 250, 252, 0.85);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border-color);
  padding: 12px 28px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
}

[data-theme="dark"] .top-header {
  background: rgba(9, 13, 22, 0.85);
}

.mobile-toggle {
  display: none;
  background: none;
  border: none;
  font-size: 1.4rem;
  color: var(--text-main);
  cursor: pointer;
  padding: 4px;
}

.search-box-wrapper {
  position: relative;
  flex: 1;
  max-width: 480px;
}

.search-box-wrapper .search-icon {
  position: absolute;
  left: 14px;
  top: 50%;
  transform: translateY(-50%);
  color: var(--text-light);
  pointer-events: none;
}

.search-input {
  width: 100%;
  padding: 10px 14px 10px 40px;
  border-radius: 9999px;
  border: 1px solid var(--border-color);
  background: var(--bg-card);
  color: var(--text-main);
  font-size: 0.92rem;
  outline: none;
  transition: all 0.2s ease;
}

.search-input:focus {
  border-color: var(--primary);
  box-shadow: 0 0 0 3px rgba(13, 148, 136, 0.15);
}

.header-actions {
  display: flex;
  align-items: center;
  gap: 12px;
}

/* Active Recall Toggle Banner */
.active-recall-toggle-btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 8px 14px;
  background: var(--bg-card);
  border: 1.5px solid var(--primary);
  color: var(--primary);
  border-radius: 9999px;
  font-weight: 700;
  font-size: 0.85rem;
  cursor: pointer;
  transition: all 0.25s cubic-bezier(0.4, 0, 0.2, 1);
  box-shadow: var(--shadow-sm);
}

.active-recall-toggle-btn:hover {
  background: var(--primary);
  color: #ffffff;
  box-shadow: 0 4px 12px rgba(13, 148, 136, 0.25);
}

.active-recall-toggle-btn.active {
  background: #0f766e;
  color: #ffffff;
  border-color: #0f766e;
  animation: pulse-glow 2s infinite;
}

@keyframes pulse-glow {
  0% { box-shadow: 0 0 0 0 rgba(13, 148, 136, 0.4); }
  70% { box-shadow: 0 0 0 10px rgba(13, 148, 136, 0); }
  100% { box-shadow: 0 0 0 0 rgba(13, 148, 136, 0); }
}

/* Page Container */
.page-container {
  padding: 24px 28px 60px;
  flex: 1;
  max-width: 1400px;
  margin: 0 auto;
  width: 100%;
}

.tab-content {
  display: none;
  animation: fadeIn 0.3s ease;
}

.tab-content.active {
  display: block;
}

@keyframes fadeIn {
  from { opacity: 0; transform: translateY(6px); }
  to { opacity: 1; transform: translateY(0); }
}

/* Section Header */
.section-banner {
  background: linear-gradient(135deg, var(--primary-dark), #1e3a8a);
  color: #ffffff;
  padding: 24px 28px;
  border-radius: var(--radius-lg);
  margin-bottom: 24px;
  box-shadow: var(--shadow-md);
  position: relative;
  overflow: hidden;
}

.section-banner::after {
  content: "中药";
  position: absolute;
  right: -10px;
  bottom: -25px;
  font-size: 9rem;
  font-weight: 900;
  color: rgba(255, 255, 255, 0.05);
  line-height: 1;
  pointer-events: none;
  user-select: none;
}

.section-banner h1 {
  font-family: var(--font-serif-zh);
  font-size: 1.85rem;
  font-weight: 800;
  margin-bottom: 6px;
  letter-spacing: 0.5px;
}

.section-banner p {
  font-size: 0.95rem;
  opacity: 0.9;
  max-width: 750px;
}

/* Chapter Filters */
.filter-pills {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-bottom: 24px;
}

.pill-btn {
  padding: 6px 14px;
  border-radius: 9999px;
  border: 1px solid var(--border-color);
  background: var(--bg-card);
  color: var(--text-muted);
  font-size: 0.85rem;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.2s ease;
}

.pill-btn:hover {
  border-color: var(--primary);
  color: var(--primary);
}

.pill-btn.active {
  background: var(--primary);
  color: #ffffff;
  border-color: var(--primary);
  box-shadow: 0 2px 6px rgba(13, 148, 136, 0.3);
}

/* Table of Contents Container */
.toc-container {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 16px 20px;
  margin-bottom: 28px;
  box-shadow: var(--shadow-sm);
}

.toc-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 12px;
  padding-bottom: 10px;
  border-bottom: 1px solid var(--border-color);
}

.toc-title {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 1.05rem;
  font-weight: 700;
  color: var(--text-main);
}

.toc-icon {
  font-size: 1.3rem;
}

#toc-count-badge {
  background: rgba(13, 148, 136, 0.12);
  color: var(--primary);
  padding: 4px 10px;
  border-radius: 9999px;
  font-size: 0.8rem;
  font-weight: 700;
}

/* Chapter Block Container */
.chapter-block {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-xl);
  padding: 24px;
  margin-bottom: 36px;
  box-shadow: var(--shadow-sm);
  transition: border-color 0.2s;
}

.chapter-block:hover {
  border-color: rgba(13, 148, 136, 0.4);
}

/* Chapter Header */
.chapter-header {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  margin-bottom: 16px;
  padding-bottom: 14px;
  border-bottom: 2px solid var(--border-color);
}

.chapter-header-main {
  display: flex;
  flex-direction: column;
  gap: 4px;
}

.chapter-number-tag {
  display: inline-flex;
  align-items: center;
  font-size: 0.78rem;
  font-weight: 800;
  color: var(--primary);
  background: rgba(13, 148, 136, 0.1);
  padding: 2px 10px;
  border-radius: 4px;
  width: fit-content;
  text-transform: uppercase;
  letter-spacing: 0.5px;
}

.chapter-title-zh {
  font-size: 1.6rem;
  font-weight: 800;
  color: var(--text-main);
  margin: 0;
  line-height: 1.25;
}

.chapter-title-th {
  font-size: 1rem;
  font-weight: 500;
  color: var(--text-muted);
}

.chapter-header-badge .badge-count {
  display: inline-flex;
  align-items: center;
  background: linear-gradient(135deg, var(--primary), var(--primary-dark));
  color: #ffffff;
  font-size: 0.82rem;
  font-weight: 700;
  padding: 6px 14px;
  border-radius: 9999px;
  box-shadow: 0 2px 6px rgba(13, 148, 136, 0.3);
  white-space: nowrap;
}

/* Chapter Overview & Cautions Collapsible Card */
.chapter-meta-details {
  background: var(--bg-body);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  margin-bottom: 24px;
  overflow: hidden;
  transition: all 0.2s;
}

.chapter-meta-summary {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 12px 16px;
  font-size: 0.92rem;
  font-weight: 700;
  color: var(--primary-dark);
  cursor: pointer;
  background: rgba(13, 148, 136, 0.05);
  user-select: none;
}

.chapter-meta-summary:hover {
  background: rgba(13, 148, 136, 0.1);
}

.chapter-meta-details[open] .chevron-icon {
  transform: rotate(180deg);
}

.chevron-icon {
  font-size: 0.75rem;
  transition: transform 0.2s;
}

.chapter-meta-content {
  padding: 16px;
  display: flex;
  flex-direction: column;
  gap: 12px;
  border-top: 1px solid var(--border-color);
}

.meta-row {
  display: flex;
  flex-direction: column;
  gap: 4px;
}

.meta-label {
  font-size: 0.88rem;
  font-weight: 800;
}

.meta-overview .meta-label {
  color: var(--primary-dark);
}

.meta-caution .meta-label {
  color: #b91c1c;
}

.meta-text {
  font-size: 0.9rem;
  line-height: 1.55;
}

.meta-text .zh {
  color: var(--text-main);
  font-weight: 600;
  margin-bottom: 2px;
}

.meta-text .th {
  color: var(--text-muted);
  font-size: 0.85rem;
}

/* Section Dividers */
.section-group {
  margin-bottom: 28px;
}

.section-group:last-child {
  margin-bottom: 0;
}

.section-header-divider {
  display: flex;
  align-items: center;
  gap: 8px;
  margin-bottom: 14px;
  padding-bottom: 6px;
  border-bottom: 1px dashed var(--border-color);
}

.sec-dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--primary);
  display: inline-block;
}

.sec-title-zh {
  font-size: 1.15rem;
  font-weight: 700;
  color: var(--text-main);
  margin: 0;
}

.sec-title-th {
  font-size: 0.88rem;
  color: var(--text-muted);
  font-weight: 500;
}

.sec-count {
  font-size: 0.8rem;
  font-weight: 700;
  color: var(--primary);
  margin-left: auto;
}

/* Flashcard Filter Row */
.fc-filter-container {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 12px;
  margin-bottom: 20px;
  flex-wrap: wrap;
}

.fc-filter-label {
  font-size: 0.95rem;
  font-weight: 700;
  color: var(--text-main);
}

.fc-chapter-select {
  padding: 8px 16px;
  border-radius: 9999px;
  border: 1.5px solid var(--primary);
  background: var(--bg-card);
  color: var(--text-main);
  font-size: 0.92rem;
  font-weight: 600;
  outline: none;
  cursor: pointer;
  transition: all 0.2s;
  max-width: 360px;
}

.fc-chapter-select:focus {
  box-shadow: 0 0 0 3px rgba(13, 148, 136, 0.2);
}

/* Herb Grid */
.herb-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(360px, 1fr));
  gap: 20px;
}

/* Herb Card */
.herb-card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 0;
  box-shadow: var(--shadow-sm);
  display: flex;
  flex-direction: column;
  transition: transform 0.2s ease, box-shadow 0.2s ease, border-color 0.2s ease;
  position: relative;
  overflow: hidden;
}

.herb-card:hover {
  transform: translateY(-3px);
  box-shadow: var(--shadow-md);
  border-color: var(--primary);
}

.herb-cover {
  position: relative;
  width: 100%;
  height: 160px;
  background: var(--bg-body);
  overflow: hidden;
  cursor: pointer;
}

.herb-cover-img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  object-position: center;
  transition: transform 0.4s cubic-bezier(0.16, 1, 0.3, 1);
  display: block;
}

.herb-card:hover .herb-cover-img {
  transform: scale(1.06);
}

.herb-cover-badge {
  position: absolute;
  bottom: 8px;
  right: 10px;
  background: rgba(15, 23, 42, 0.72);
  backdrop-filter: blur(6px);
  color: #ffffff;
  font-size: 0.72rem;
  font-weight: 600;
  padding: 3px 9px;
  border-radius: 9999px;
  pointer-events: none;
  transition: opacity 0.2s ease, background 0.2s ease;
  opacity: 0.85;
}

.herb-card:hover .herb-cover-badge {
  opacity: 1;
  background: rgba(13, 148, 136, 0.9);
}

.herb-card-body {
  padding: 20px;
  display: flex;
  flex-direction: column;
  flex: 1;
}

.herb-card-header {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  margin-bottom: 14px;
  padding-bottom: 12px;
  border-bottom: 1px solid var(--border-color);
}

.herb-names {
  display: flex;
  flex-direction: column;
}

.herb-name-zh {
  font-family: var(--font-serif-zh);
  font-size: 1.65rem;
  font-weight: 800;
  color: var(--text-main);
  line-height: 1.2;
}

.herb-pinyin {
  font-size: 0.9rem;
  font-family: var(--font-mono);
  font-weight: 600;
  color: var(--primary);
}

.herb-name-th {
  font-size: 0.88rem;
  color: var(--text-muted);
  margin-top: 2px;
}

.herb-badges {
  display: flex;
  flex-direction: column;
  align-items: flex-end;
  gap: 6px;
}

.badge-level {
  font-family: var(--font-serif-zh);
  font-size: 0.75rem;
  font-weight: 700;
  padding: 2px 8px;
  border-radius: 4px;
  letter-spacing: 0.5px;
  display: inline-flex;
  align-items: center;
  gap: 4px;
}

.badge-level .level-stars {
  font-size: 0.72rem;
  letter-spacing: -1px;
}

/* Three level tiers: 掌握 (3 stars - imperial cinnabar red), 熟悉 (2 stars - antique gold), 了解 (1 star - jade green) */
.badge-level[data-level="掌握"], .badge-level.level-master {
  background: rgba(140, 29, 24, 0.08);
  color: #8C1D18;
  border: 1.5px solid #8C1D18;
  box-shadow: inset 0 0 0 1px rgba(140, 29, 24, 0.12);
}

.badge-level[data-level="熟悉"], .badge-level.level-familiar {
  background: rgba(197, 160, 89, 0.15);
  color: #8A641A;
  border: 1.5px solid #B88E3E;
  box-shadow: inset 0 0 0 1px rgba(197, 160, 89, 0.2);
}

.badge-level[data-level="了解"], .badge-level.level-understand {
  background: rgba(38, 110, 82, 0.08);
  color: #1F6B4E;
  border: 1.5px solid #2E8A65;
  box-shadow: inset 0 0 0 1px rgba(38, 110, 82, 0.12);
}

[data-theme="dark"] .badge-level[data-level="掌握"] {
  background: rgba(220, 60, 50, 0.15);
  color: #E65A50;
  border-color: #E65A50;
}

[data-theme="dark"] .badge-level[data-level="熟悉"] {
  background: rgba(232, 201, 123, 0.15);
  color: #E8C97B;
  border-color: #C5A059;
}

[data-theme="dark"] .badge-level[data-level="了解"] {
  background: rgba(72, 187, 140, 0.15);
  color: #5FD19F;
  border-color: #3A8E6E;
}


.badge-chapter {
  font-size: 0.74rem;
  font-weight: 600;
  padding: 2px 7px;
  border-radius: 4px;
  background: var(--accent-gold-light);
  color: var(--accent-gold-dark);
  border: 1px solid var(--accent-gold);
}

.star-btn {
  background: none;
  border: none;
  font-size: 1.2rem;
  color: var(--text-light);
  cursor: pointer;
  transition: transform 0.15s, color 0.15s;
  padding: 2px;
}

.star-btn:hover {
  transform: scale(1.2);
}

.star-btn.starred {
  color: #eab308;
}

/* Herb Body Grid */
.herb-props {
  display: flex;
  flex-direction: column;
  gap: 10px;
  flex: 1;
}

.prop-row {
  display: flex;
  flex-direction: column;
  gap: 3px;
}

.prop-label {
  font-size: 0.78rem;
  font-weight: 700;
  color: var(--primary-dark);
  text-transform: uppercase;
  letter-spacing: 0.5px;
  display: flex;
  align-items: center;
  gap: 6px;
}

[data-theme="dark"] .prop-label {
  color: var(--primary);
}

.prop-value-zh {
  font-size: 0.95rem;
  font-weight: 600;
  color: var(--text-main);
  line-height: 1.4;
}

.prop-value-th {
  font-size: 0.85rem;
  color: var(--text-muted);
  line-height: 1.4;
}

.herb-exam-box {
  background: var(--accent-gold-light);
  border-left: 4px solid var(--accent-gold);
  padding: 10px 12px;
  border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
  margin-top: 10px;
  font-size: 0.85rem;
  color: #78350f;
  line-height: 1.4;
}

[data-theme="dark"] .herb-exam-box {
  background: #3b2203;
  color: #fde68a;
  border-color: #f59e0b;
}

.herb-caution-box {
  background: var(--danger-light);
  border-left: 4px solid var(--danger);
  padding: 8px 12px;
  border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
  margin-top: 8px;
  font-size: 0.82rem;
  color: var(--danger-text);
  line-height: 1.4;
}

[data-theme="dark"] .herb-caution-box {
  background: #3c1414;
  color: #fca5a5;
  border-color: #f87171;
}

/* ==========================================================================
   ACTIVE RECALL (Cloze / Blur & Reveal Mode)
   ========================================================================== */
.active-recall-on .recall-blur {
  filter: blur(7px);
  background: rgba(148, 163, 184, 0.25);
  border-radius: 4px;
  cursor: pointer;
  user-select: none;
  transition: all 0.25s ease;
  position: relative;
  display: inline-block;
  min-width: 80px;
}

.active-recall-on .recall-blur:hover {
  filter: blur(4px);
  background: rgba(148, 163, 184, 0.4);
}

.active-recall-on .recall-blur.revealed {
  filter: none !important;
  background: transparent !important;
  user-select: text !important;
  cursor: default;
}

.recall-hint-badge {
  display: none;
}

.active-recall-on .recall-hint-badge {
  display: inline-block;
  font-size: 0.7rem;
  color: var(--primary);
  background: var(--primary-light);
  padding: 1px 6px;
  border-radius: 3px;
  margin-left: 6px;
  font-weight: 600;
  cursor: pointer;
}

/* ==========================================================================
   FLASHCARD SYSTEM (3D Flip & Leitner SRS)
   ========================================================================== */
.flashcard-wrapper {
  max-width: 680px;
  margin: 0 auto;
  perspective: 1200px;
}

.flashcard-container {
  width: 100%;
  min-height: 420px;
  position: relative;
  cursor: pointer;
  transform-style: preserve-3d;
  transition: transform 0.6s cubic-bezier(0.4, 0, 0.2, 1);
  border-radius: var(--radius-lg);
}

.flashcard-container.is-flipped {
  transform: rotateY(180deg);
}

.card-face {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  backface-visibility: hidden;
  -webkit-backface-visibility: hidden;
  border-radius: var(--radius-lg);
  background: var(--bg-card);
  border: 2px solid var(--border-color);
  box-shadow: var(--shadow-lg);
  padding: 32px;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
}

.card-face.card-back {
  transform: rotateY(180deg);
  overflow-y: auto;
  border-color: var(--primary);
}

.fc-front-content {
  text-align: center;
  margin: auto 0;
}

.fc-badge {
  display: inline-block;
  font-size: 0.85rem;
  font-weight: 700;
  padding: 4px 12px;
  border-radius: 9999px;
  background: var(--primary-light);
  color: var(--primary-text);
  margin-bottom: 20px;
}

.fc-name-zh {
  font-size: 3.5rem;
  font-weight: 900;
  color: var(--text-main);
  margin-bottom: 6px;
  letter-spacing: 2px;
}

.fc-pinyin {
  font-size: 1.4rem;
  font-family: var(--font-mono);
  color: var(--primary);
  margin-bottom: 12px;
}

.fc-prompt {
  font-size: 0.95rem;
  color: var(--text-muted);
  background: var(--bg-sidebar);
  padding: 10px 16px;
  border-radius: var(--radius-md);
  margin-top: 24px;
}

.fc-flip-hint {
  text-align: center;
  font-size: 0.8rem;
  color: var(--text-light);
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 6px;
}

.fc-back-header {
  border-bottom: 1px solid var(--border-color);
  padding-bottom: 14px;
  margin-bottom: 16px;
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.fc-back-title-zh {
  font-size: 1.8rem;
  font-weight: 800;
}

.fc-back-title-th {
  font-size: 1rem;
  color: var(--text-muted);
}

.fc-back-body {
  display: flex;
  flex-direction: column;
  gap: 14px;
}

/* Flashcard Controls */
.flashcard-actions {
  display: flex;
  justify-content: center;
  align-items: center;
  gap: 12px;
  margin-top: 28px;
}

.rating-btn {
  flex: 1;
  max-width: 140px;
  padding: 12px 14px;
  border-radius: var(--radius-md);
  font-weight: 700;
  font-size: 0.88rem;
  cursor: pointer;
  border: 1px solid transparent;
  transition: all 0.2s ease;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 2px;
}

.rating-btn .sub {
  font-size: 0.72rem;
  font-weight: 500;
  opacity: 0.85;
}

.btn-again {
  background: var(--danger-light);
  color: var(--danger-text);
  border-color: var(--danger);
}
.btn-again:hover { background: var(--danger); color: #fff; }

.btn-hard {
  background: var(--accent-gold-light);
  color: #78350f;
  border-color: var(--accent-gold);
}
.btn-hard:hover { background: var(--accent-gold); color: #fff; }

.btn-good {
  background: var(--primary-light);
  color: var(--primary-text);
  border-color: var(--primary);
}
.btn-good:hover { background: var(--primary); color: #fff; }

.btn-easy {
  background: var(--success-light);
  color: #065f46;
  border-color: var(--success);
}
.btn-easy:hover { background: var(--success); color: #fff; }

.fc-stats-bar {
  display: flex;
  justify-content: space-between;
  align-items: center;
  max-width: 680px;
  margin: 0 auto 16px;
  font-size: 0.88rem;
  color: var(--text-muted);
}

/* ==========================================================================
   EXAM QUIZ SIMULATOR
   ========================================================================== */
.quiz-wrapper {
  max-width: 780px;
  margin: 0 auto;
}

.quiz-card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 32px;
  box-shadow: var(--shadow-md);
  margin-bottom: 24px;
}

.quiz-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 20px;
  padding-bottom: 12px;
  border-bottom: 1px solid var(--border-color);
}

.quiz-progress-label {
  font-size: 0.85rem;
  font-weight: 700;
  color: var(--primary);
}

.quiz-question-box {
  margin-bottom: 28px;
}

.quiz-question-zh {
  font-family: var(--font-serif-zh);
  font-size: 1.3rem;
  font-weight: 700;
  color: var(--text-main);
  line-height: 1.5;
  margin-bottom: 8px;
}

.quiz-question-th {
  font-size: 0.95rem;
  color: var(--text-muted);
  line-height: 1.5;
  background: var(--bg-sidebar);
  padding: 8px 14px;
  border-radius: var(--radius-sm);
}

.quiz-options {
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.quiz-opt-btn {
  width: 100%;
  padding: 14px 18px;
  background: var(--bg-main);
  border: 1.5px solid var(--border-color);
  border-radius: var(--radius-md);
  color: var(--text-main);
  font-size: 1rem;
  font-weight: 600;
  text-align: left;
  cursor: pointer;
  transition: all 0.2s ease;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.quiz-opt-btn:hover:not(:disabled) {
  border-color: var(--primary);
  background: rgba(13, 148, 136, 0.05);
}

.quiz-opt-btn.correct {
  background: var(--success-light) !important;
  border-color: var(--success) !important;
  color: #065f46 !important;
  box-shadow: 0 0 0 2px var(--success);
}

.quiz-opt-btn.incorrect {
  background: var(--danger-light) !important;
  border-color: var(--danger) !important;
  color: var(--danger-text) !important;
  box-shadow: 0 0 0 2px var(--danger);
}

.quiz-explanation {
  margin-top: 24px;
  padding: 18px 20px;
  background: var(--bg-sidebar);
  border-left: 4px solid var(--primary);
  border-radius: 0 var(--radius-md) var(--radius-md) 0;
  display: none;
}

.quiz-explanation.show {
  display: block;
  animation: fadeIn 0.3s ease;
}

.quiz-explanation h4 {
  font-size: 0.95rem;
  font-weight: 700;
  color: var(--primary);
  margin-bottom: 6px;
}

.quiz-explanation p {
  font-size: 0.9rem;
  line-height: 1.5;
  margin-bottom: 6px;
}

.quiz-footer {
  display: flex;
  justify-content: flex-end;
  margin-top: 24px;
}

.btn-primary {
  background: var(--primary);
  color: #ffffff;
  border: none;
  padding: 12px 24px;
  border-radius: var(--radius-md);
  font-size: 0.95rem;
  font-weight: 700;
  cursor: pointer;
  transition: all 0.2s;
  box-shadow: var(--shadow-sm);
}

.btn-primary:hover {
  background: var(--primary-dark);
  box-shadow: var(--shadow-md);
}

/* Quiz Score Card */
.quiz-score-card {
  text-align: center;
  padding: 40px 24px;
}

.score-circle {
  width: 120px;
  height: 120px;
  border-radius: 50%;
  background: var(--primary-light);
  color: var(--primary-text);
  font-size: 2.2rem;
  font-weight: 900;
  display: flex;
  align-items: center;
  justify-content: center;
  margin: 0 auto 20px;
  border: 4px solid var(--primary);
}

/* ==========================================================================
   HERB COMPARISONS TABLE (鉴别用药)
   ========================================================================== */
.comp-card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 24px;
  margin-bottom: 24px;
  box-shadow: var(--shadow-sm);
}

.comp-header {
  margin-bottom: 16px;
  border-bottom: 1px solid var(--border-color);
  padding-bottom: 12px;
}

.comp-title {
  font-size: 1.4rem;
  font-weight: 800;
  color: var(--primary-dark);
}

[data-theme="dark"] .comp-title {
  color: var(--primary);
}

.comp-summary {
  font-size: 0.92rem;
  color: var(--text-muted);
  margin-top: 4px;
  line-height: 1.5;
}

.comp-table {
  width: 100%;
  border-collapse: collapse;
  margin-top: 12px;
}

.comp-table th, .comp-table td {
  padding: 12px 16px;
  border: 1px solid var(--border-color);
  text-align: left;
  font-size: 0.92rem;
  line-height: 1.5;
}

.comp-table th {
  background: var(--bg-sidebar);
  font-weight: 700;
  color: var(--text-main);
}

/* ==========================================================================
   GENERAL THEORY (总论)
   ========================================================================== */
.theory-block {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 28px;
  margin-bottom: 24px;
  box-shadow: var(--shadow-sm);
}

.theory-block h2 {
  font-size: 1.4rem;
  font-weight: 800;
  color: var(--primary-dark);
  margin-bottom: 6px;
}

[data-theme="dark"] .theory-block h2 {
  color: var(--primary);
}

.theory-block .sub-desc {
  font-size: 0.9rem;
  color: var(--text-muted);
  margin-bottom: 20px;
}

.history-card {
  border-left: 4px solid var(--primary);
  background: var(--bg-sidebar);
  padding: 16px 20px;
  border-radius: 0 var(--radius-md) var(--radius-md) 0;
  margin-bottom: 16px;
}

.history-card-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 8px;
  flex-wrap: wrap;
  gap: 8px;
}

.history-book {
  font-size: 1.15rem;
  font-weight: 800;
  color: var(--text-main);
}

.history-meta {
  font-size: 0.85rem;
  color: var(--primary-dark);
  font-weight: 600;
}

.history-significance {
  font-size: 0.92rem;
  line-height: 1.5;
  margin-bottom: 6px;
}

.history-exam {
  font-size: 0.85rem;
  color: var(--accent-gold);
  font-weight: 600;
}

.taboo-box {
  background: var(--danger-light);
  border: 1.5px solid var(--danger);
  border-radius: var(--radius-md);
  padding: 20px;
  margin-top: 16px;
}

.taboo-poem {
  font-size: 1.1rem;
  font-weight: 700;
  font-family: var(--font-mono);
  color: var(--danger-text);
  line-height: 1.6;
  white-space: pre-line;
  margin-bottom: 14px;
}

/* Anki Export UI */
.anki-export-box {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 32px;
  box-shadow: var(--shadow-sm);
  max-width: 800px;
  margin: 0 auto;
}

.anki-guide-steps {
  margin: 20px 0;
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.guide-step {
  display: flex;
  align-items: flex-start;
  gap: 12px;
  font-size: 0.92rem;
  line-height: 1.5;
}

.step-num {
  width: 26px;
  height: 26px;
  border-radius: 50%;
  background: var(--primary);
  color: #fff;
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 700;
  font-size: 0.8rem;
  flex-shrink: 0;
}

/* Flashcard Image */
.fc-back-img {
  width: 68px;
  height: 68px;
  border-radius: 12px;
  object-fit: cover;
  border: 2px solid var(--border-color);
  box-shadow: var(--shadow-sm);
  flex-shrink: 0;
  background: var(--bg-body);
}

/* Image Lightbox Modal */
.image-modal-backdrop {
  position: fixed;
  inset: 0;
  background: rgba(15, 23, 42, 0.78);
  backdrop-filter: blur(8px);
  z-index: 9999;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 20px;
  animation: modalFadeIn 0.2s ease-out forwards;
}

.image-modal-dialog {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-xl);
  max-width: 620px;
  width: 100%;
  overflow: hidden;
  position: relative;
  box-shadow: 0 25px 50px -12px rgba(0, 0, 0, 0.4);
  animation: modalSlideUp 0.25s cubic-bezier(0.16, 1, 0.3, 1) forwards;
}

.modal-close-btn {
  position: absolute;
  top: 12px;
  right: 12px;
  width: 36px;
  height: 36px;
  border-radius: 50%;
  background: rgba(0, 0, 0, 0.55);
  color: #ffffff;
  border: none;
  font-size: 1.5rem;
  line-height: 1;
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  z-index: 10;
  transition: all 0.2s ease;
}

.modal-close-btn:hover {
  background: var(--danger);
  transform: rotate(90deg);
}

.modal-img-wrapper {
  width: 100%;
  max-height: 440px;
  background: #0f172a;
  display: flex;
  align-items: center;
  justify-content: center;
  overflow: hidden;
}

.modal-full-img {
  width: 100%;
  max-height: 440px;
  object-fit: contain;
  display: block;
}

.modal-info {
  padding: 18px 24px;
  background: var(--bg-card);
  border-top: 1px solid var(--border-color);
}

.modal-title-zh {
  font-size: 1.6rem;
  font-weight: 800;
  color: var(--text-main);
}

.modal-sub {
  font-size: 0.95rem;
  color: var(--text-muted);
  margin-top: 4px;
}

@keyframes modalFadeIn {
  from { opacity: 0; }
  to { opacity: 1; }
}

@keyframes modalSlideUp {
  from { opacity: 0; transform: translateY(16px) scale(0.97); }
  to { opacity: 1; transform: translateY(0) scale(1); }
}

/* Responsive Breakpoints */
@media (max-width: 900px) {
  .sidebar {
    position: fixed;
    left: 0;
    top: 0;
    transform: translateX(-100%);
    box-shadow: var(--shadow-lg);
  }
  .sidebar.open {
    transform: translateX(0);
  }
  .mobile-toggle {
    display: block;
  }
  .top-header {
    padding: 10px 16px;
  }
  .page-container {
    padding: 16px;
  }
  .herb-grid {
    grid-template-columns: 1fr;
  }
}

/* Database Status Badge */
.db-status-badge {
  font-size: 0.76rem;
  padding: 5px 10px;
  border-radius: 9999px;
  text-align: center;
  margin-bottom: 10px;
  font-weight: 600;
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  color: var(--text-muted);
  display: block;
  width: 100%;
  box-sizing: border-box;
  transition: all 0.3s ease;
}

.db-status-badge.connected {
  background: #ecfdf5;
  color: #065f46;
  border-color: #a7f3d0;
}

.db-status-badge.local {
  background: #f1f5f9;
  color: #475569;
  border-color: #cbd5e1;
}

[data-theme="dark"] .db-status-badge.connected {
  background: #064e3b;
  color: #a7f3d0;
  border-color: #047857;
}

[data-theme="dark"] .db-status-badge.local {
  background: #1e293b;
  color: #94a3b8;
  border-color: #334155;
}

/* ==========================================================================
   Ancient Chinese / Three Kingdoms Styling & Apple Typography Components
   ========================================================================== */

/* User Profile Badge in Sidebar */
.user-profile-badge {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 10px 14px;
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  margin-bottom: 8px;
  box-shadow: var(--shadow-sm);
}

.user-avatar-seal {
  width: 36px;
  height: 36px;
  border-radius: 6px;
  background: rgba(140, 29, 24, 0.08);
  border: 1.5px solid var(--primary);
  color: var(--primary);
  font-family: var(--font-serif-zh);
  font-size: 1.1rem;
  font-weight: 900;
  display: flex;
  align-items: center;
  justify-content: center;
  box-shadow: inset 0 0 0 1px rgba(140, 29, 24, 0.2);
  flex-shrink: 0;
}

.user-meta {
  flex: 1;
  min-width: 0;
}

.user-display-name {
  font-size: 0.88rem;
  font-weight: 700;
  color: var(--text-main);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
  letter-spacing: -0.01em;
}

.user-handle {
  font-size: 0.75rem;
  color: var(--text-muted);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.logout-btn {
  background: none;
  border: 1px solid var(--border-color);
  color: var(--danger-text);
  font-size: 0.76rem;
  font-weight: 700;
  padding: 4px 8px;
  border-radius: var(--radius-sm);
  cursor: pointer;
  transition: all 0.2s;
  font-family: var(--font-sans);
}

.logout-btn:hover {
  background: var(--danger-light);
  border-color: var(--danger);
}

/* Admin Portal Link in Sidebar */
.admin-portal-link {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 6px;
  width: 100%;
  padding: 8px 12px;
  background: var(--bg-card);
  border: 1px dashed var(--accent-gold);
  border-radius: var(--radius-sm);
  color: var(--accent-gold-dark);
  font-size: 0.82rem;
  font-weight: 700;
  text-decoration: none;
  cursor: pointer;
  transition: all 0.2s;
  box-sizing: border-box;
}

.admin-portal-link:hover {
  background: var(--accent-gold-light);
  border-style: solid;
}

/* Site Announcement Banner */
.site-announcement-banner {
  display: flex;
  align-items: center;
  gap: 12px;
  background: linear-gradient(90deg, var(--bg-card), var(--bg-sidebar));
  border: 1px solid var(--accent-gold);
  border-left: 4px solid var(--primary);
  border-radius: var(--radius-md);
  padding: 12px 18px;
  margin-bottom: 20px;
  box-shadow: var(--shadow-sm);
  position: relative;
  overflow: hidden;
}

.announcement-icon {
  font-size: 1.3rem;
  flex-shrink: 0;
}

.announcement-text {
  font-size: 0.92rem;
  font-weight: 600;
  color: var(--text-main);
  line-height: 1.4;
  letter-spacing: -0.01em;
}

/* Authentication Gate Modal */
.auth-modal-backdrop {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: rgba(18, 16, 14, 0.78);
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  z-index: 9999;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 20px;
  animation: authFadeIn 0.3s ease-out;
}

@keyframes authFadeIn {
  from { opacity: 0; }
  to { opacity: 1; }
}

.auth-modal-dialog {
  background: var(--bg-card);
  border: 2px solid var(--accent-gold);
  border-radius: var(--radius-lg);
  width: 100%;
  max-width: 440px;
  box-shadow: 0 20px 40px rgba(0, 0, 0, 0.35), 0 0 0 1px rgba(197, 160, 89, 0.2);
  padding: 32px 28px;
  position: relative;
  overflow: hidden;
}

.auth-modal-dialog::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 4px;
  background: linear-gradient(90deg, var(--primary), var(--accent-gold), var(--primary));
}

.auth-modal-header {
  text-align: center;
  margin-bottom: 24px;
}

.auth-seal-logo {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 64px;
  height: 64px;
  border: 2px solid var(--accent-gold);
  border-radius: 50%;
  background: #ffffff;
  margin-bottom: 12px;
  box-shadow: 0 4px 14px rgba(184, 134, 11, 0.25);
  overflow: hidden;
  padding: 2px;
}

.auth-modal-logo {
  width: 100%;
  height: 100%;
  object-fit: cover;
  border-radius: 50%;
  display: block;
}

.auth-title {
  font-family: var(--font-serif-zh);
  font-size: 1.38rem;
  font-weight: 800;
  color: var(--primary-dark);
  margin-bottom: 6px;
  letter-spacing: 0.5px;
}

.auth-subtitle {
  font-size: 0.86rem;
  color: var(--text-muted);
  line-height: 1.4;
}

.auth-tabs {
  display: flex;
  background: var(--bg-sidebar);
  border-radius: var(--radius-md);
  padding: 4px;
  margin-bottom: 20px;
  border: 1px solid var(--border-color);
}

.auth-tab-btn {
  flex: 1;
  padding: 9px 12px;
  border: none;
  background: none;
  border-radius: var(--radius-sm);
  font-size: 0.88rem;
  font-weight: 700;
  color: var(--text-muted);
  cursor: pointer;
  transition: all 0.2s ease;
  font-family: var(--font-sans);
}

.auth-tab-btn.active {
  background: var(--bg-card);
  color: var(--primary);
  box-shadow: var(--shadow-sm);
  border: 1px solid var(--border-color);
}

.auth-alert {
  padding: 10px 14px;
  border-radius: var(--radius-md);
  font-size: 0.85rem;
  line-height: 1.4;
  margin-bottom: 18px;
  animation: authFadeIn 0.2s ease;
}

.auth-alert.error {
  background: var(--danger-light);
  border: 1px solid var(--danger);
  color: var(--danger-text);
}

.auth-alert.success {
  background: var(--success-light);
  border: 1px solid var(--success);
  color: var(--success);
}

.auth-alert.info {
  background: var(--accent-gold-light);
  border: 1px solid var(--accent-gold);
  color: var(--accent-gold-dark);
}

.auth-form {
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.form-group {
  display: flex;
  flex-direction: column;
  gap: 6px;
  text-align: left;
}

.form-group label {
  font-size: 0.82rem;
  font-weight: 700;
  color: var(--text-main);
  letter-spacing: -0.01em;
}

.input-wrap {
  position: relative;
  display: flex;
  align-items: center;
}

.input-icon {
  position: absolute;
  left: 12px;
  font-size: 1rem;
  pointer-events: none;
  opacity: 0.7;
}

.input-wrap input {
  width: 100%;
  padding: 11px 14px 11px 38px;
  background: var(--bg-elevated);
  border: 1.5px solid var(--border-color);
  border-radius: var(--radius-md);
  color: var(--text-main);
  font-size: 0.92rem;
  font-family: var(--font-sans);
  transition: all 0.2s ease;
  outline: none;
}

.input-wrap input:focus {
  border-color: var(--accent-gold);
  box-shadow: 0 0 0 3px rgba(197, 160, 89, 0.2);
}

.auth-submit-btn {
  background: linear-gradient(135deg, var(--primary), var(--primary-dark));
  color: #FFFFFF;
  border: 1px solid rgba(197, 160, 89, 0.4);
  padding: 12px 20px;
  border-radius: var(--radius-md);
  font-size: 0.95rem;
  font-weight: 700;
  cursor: pointer;
  transition: all 0.2s ease;
  font-family: var(--font-sans);
  margin-top: 4px;
  box-shadow: 0 4px 12px rgba(140, 29, 24, 0.25);
}

.auth-submit-btn:hover {
  transform: translateY(-1px);
  box-shadow: 0 6px 16px rgba(140, 29, 24, 0.35);
}

.auth-footer-prompt {
  text-align: center;
  font-size: 0.82rem;
  color: var(--text-muted);
  margin-top: 8px;
}

.auth-footer-prompt a {
  color: var(--primary);
  font-weight: 700;
  text-decoration: underline;
  cursor: pointer;
}

.auth-admin-hint {
  text-align: center;
  font-size: 0.78rem;
  color: var(--text-light);
  margin-top: 20px;
  padding-top: 14px;
  border-top: 1px solid var(--border-color);
}

.auth-admin-hint a {
  color: var(--accent-gold-dark);
  font-weight: 600;
  text-decoration: none;
}

.auth-admin-hint a:hover {
  text-decoration: underline;
}

/* ==========================================================================
   Quiz Simulator Enhancements: Sets Selector & Custom Exam Generator
   ========================================================================== */

.quiz-controls-panel {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 16px;
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: 16px 20px;
  margin-bottom: 24px;
  box-shadow: var(--shadow-sm);
  box-sizing: border-box;
}

.quiz-set-selector-wrap {
  display: flex;
  align-items: center;
  gap: 12px;
  flex: 1 1 360px;
  min-width: 0;
  max-width: 100%;
}

.quiz-set-selector-wrap label {
  font-size: 0.88rem;
  color: var(--text-main);
  white-space: nowrap;
  flex-shrink: 0;
}

.quiz-set-select {
  flex: 1 1 auto;
  min-width: 0;
  max-width: 100%;
  width: 100%;
  padding: 10px 14px;
  background: var(--bg-elevated);
  border: 1.5px solid var(--border-color);
  border-radius: var(--radius-sm);
  color: var(--text-main);
  font-size: 0.88rem;
  font-family: var(--font-sans);
  outline: none;
  cursor: pointer;
  text-overflow: ellipsis;
  overflow: hidden;
  white-space: nowrap;
  box-sizing: border-box;
  transition: border-color 0.2s, box-shadow 0.2s;
}

.quiz-set-select:focus {
  border-color: var(--accent-gold);
  box-shadow: 0 0 0 2px rgba(197, 160, 89, 0.2);
}

.btn-custom-exam {
  white-space: nowrap;
  flex-shrink: 0;
  background: linear-gradient(135deg, var(--accent-gold), var(--accent-gold-dark));
  color: #FFFFFF;
  border: none;
  padding: 10px 18px;
  border-radius: var(--radius-md);
  font-size: 0.88rem;
  font-weight: 700;
  cursor: pointer;
  transition: all 0.2s;
  box-shadow: 0 2px 8px rgba(197, 160, 89, 0.3);
  font-family: var(--font-sans);
}

.btn-custom-exam:hover {
  transform: translateY(-1px);
  box-shadow: 0 4px 12px rgba(197, 160, 89, 0.45);
}

/* Language Switcher Segmented Control */
.lang-switcher-control {
  display: inline-flex;
  align-items: center;
  background: var(--bg-elevated);
  border: 1.5px solid var(--border-color);
  border-radius: var(--radius-pill);
  padding: 3px;
  box-shadow: var(--shadow-sm);
  gap: 2px;
}

.lang-switch-btn {
  display: inline-flex;
  align-items: center;
  gap: 5px;
  background: transparent;
  border: none;
  outline: none;
  color: var(--text-muted);
  font-family: var(--font-sans);
  font-size: 0.84rem;
  font-weight: 600;
  padding: 6px 14px;
  border-radius: var(--radius-pill);
  cursor: pointer;
  transition: all 0.2s cubic-bezier(0.4, 0, 0.2, 1);
  white-space: nowrap;
}

.lang-switch-btn:hover {
  color: var(--text-main);
}

.lang-switch-btn.active {
  background: var(--accent-gold);
  color: #FFFFFF;
  font-weight: 700;
  box-shadow: 0 2px 8px rgba(197, 160, 89, 0.4);
}

[data-theme="dark"] .lang-switch-btn.active {
  background: var(--accent-gold);
  color: #12100E;
  font-weight: 700;
}

/* Custom Exam Generator Modal */
.exam-modal-backdrop {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: rgba(18, 16, 14, 0.75);
  backdrop-filter: blur(6px);
  -webkit-backdrop-filter: blur(6px);
  z-index: 10000;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 20px;
  animation: authFadeIn 0.3s ease;
}

.exam-modal-dialog {
  background: var(--bg-card);
  border: 2px solid var(--accent-gold);
  border-radius: var(--radius-lg);
  width: 100%;
  max-width: 620px;
  max-height: 90vh;
  overflow-y: auto;
  box-shadow: 0 24px 48px rgba(0, 0, 0, 0.35);
  padding: 30px;
  position: relative;
}

.exam-modal-header {
  margin-bottom: 22px;
  padding-right: 28px;
}

.exam-modal-tag {
  display: inline-block;
  font-size: 0.74rem;
  font-weight: 700;
  background: var(--accent-gold-light);
  color: var(--accent-gold-dark);
  border: 1px solid var(--accent-gold);
  padding: 2px 8px;
  border-radius: 4px;
  margin-bottom: 8px;
}

.exam-modal-header h3 {
  font-family: var(--font-serif-zh);
  font-size: 1.4rem;
  font-weight: 800;
  color: var(--primary-dark);
  margin-bottom: 6px;
}

.exam-modal-header p {
  font-size: 0.88rem;
  color: var(--text-muted);
  line-height: 1.45;
}

.exam-gen-form {
  display: flex;
  flex-direction: column;
  gap: 20px;
}

.gen-pill-group {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-top: 6px;
}

.gen-pill {
  padding: 7px 14px;
  background: var(--bg-sidebar);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-sm);
  color: var(--text-main);
  font-size: 0.84rem;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.2s ease;
  font-family: var(--font-sans);
}

.gen-pill:hover {
  border-color: var(--accent-gold);
  background: var(--accent-gold-light);
}

.gen-pill.active {
  background: var(--primary);
  border-color: var(--primary-dark);
  color: #FFFFFF;
  box-shadow: 0 2px 8px rgba(140, 29, 24, 0.3);
}

.btn-generate-submit {
  width: 100%;
  padding: 13px;
  font-size: 1rem;
  font-weight: 700;
}

/* ==========================================================================
   USER PROFILE STATS BUTTON
   ========================================================================== */
.user-profile-btns {
  display: flex;
  align-items: center;
  gap: 6px;
}

.btn-user-stats {
  padding: 4px 7px;
  background: rgba(197, 160, 89, 0.15);
  border: 1px solid var(--accent-gold);
  border-radius: var(--radius-sm);
  color: var(--accent-gold-dark);
  font-size: 0.82rem;
  font-weight: 700;
  cursor: pointer;
  transition: all 0.2s;
}

.btn-user-stats:hover {
  background: var(--accent-gold);
  color: #FFFFFF;
}

/* ==========================================================================
   QUIZ CONTROLS ACTIONS & PREV ATTEMPT BANNER
   ========================================================================== */
.quiz-controls-actions {
  display: flex;
  align-items: center;
  gap: 10px;
  flex-wrap: wrap;
  flex-shrink: 0;
}

.btn-history-exam {
  white-space: nowrap;
  flex-shrink: 0;
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 10px 18px;
  background: var(--bg-card);
  border: 1.5px solid var(--accent-gold);
  border-radius: var(--radius-md);
  color: var(--primary-dark);
  font-size: 0.88rem;
  font-weight: 700;
  cursor: pointer;
  transition: all 0.2s;
  box-shadow: var(--shadow-sm);
  font-family: var(--font-sans);
}

@media (max-width: 960px) {
  .quiz-controls-panel {
    flex-direction: column;
    align-items: stretch;
    gap: 14px;
  }
  .quiz-set-selector-wrap {
    width: 100%;
    flex: 1 1 100%;
  }
  .quiz-controls-actions {
    width: 100%;
    justify-content: flex-start;
  }
}

.btn-history-exam:hover {
  background: var(--accent-gold-light);
  border-color: var(--primary);
  transform: translateY(-1px);
}

.quiz-prev-attempt-banner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  padding: 12px 18px;
  background: rgba(197, 160, 89, 0.12);
  border: 1.5px solid var(--accent-gold);
  border-radius: var(--radius-md);
  margin-bottom: 20px;
  font-size: 0.9rem;
  animation: authFadeIn 0.3s ease;
}

.quiz-prev-attempt-banner .prev-attempt-info {
  display: flex;
  align-items: center;
  gap: 10px;
  flex-wrap: wrap;
}

.prev-badge-score {
  font-weight: 800;
  color: var(--primary);
  background: rgba(140, 29, 24, 0.08);
  padding: 3px 8px;
  border-radius: 4px;
  border: 1px solid var(--primary);
}

.btn-review-attempt {
  padding: 6px 14px;
  background: var(--primary);
  color: #FFFFFF;
  border: none;
  border-radius: var(--radius-sm);
  font-weight: 600;
  font-size: 0.82rem;
  cursor: pointer;
  transition: background 0.2s;
  white-space: nowrap;
}

.btn-review-attempt:hover {
  background: var(--primary-dark);
}

/* ==========================================================================
   USER ANALYTICS MODAL & DASHBOARD
   ========================================================================== */
.analytics-modal-backdrop,
.review-modal-backdrop {
  position: fixed;
  top: 0;
  left: 0;
  width: 100vw;
  height: 100vh;
  background: rgba(19, 17, 15, 0.75);
  backdrop-filter: blur(8px);
  z-index: 9999;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 20px;
  box-sizing: border-box;
  animation: authFadeIn 0.25s ease;
}

.analytics-modal-dialog,
.review-modal-dialog {
  background: var(--bg-card);
  width: 100%;
  max-width: 960px;
  max-height: 90vh;
  overflow-y: auto;
  border-radius: var(--radius-lg);
  border: 2px solid var(--accent-gold);
  box-shadow: 0 20px 50px rgba(0, 0, 0, 0.4);
  padding: 30px;
  position: relative;
  box-sizing: border-box;
}

.analytics-modal-header,
.review-modal-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 18px;
  border-bottom: 2px solid var(--accent-gold);
  padding-bottom: 18px;
  margin-bottom: 24px;
}

.analytics-seal-logo {
  width: 54px;
  height: 54px;
  border: 2px solid var(--accent-gold);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  background: #ffffff;
  box-shadow: 0 2px 10px rgba(0, 0, 0, 0.08);
  flex-shrink: 0;
  overflow: hidden;
  padding: 2px;
}

.analytics-modal-logo {
  width: 100%;
  height: 100%;
  object-fit: cover;
  border-radius: 50%;
  display: block;
}

.analytics-tag,
.review-badge-tag {
  display: inline-block;
  font-size: 0.74rem;
  font-weight: 700;
  color: var(--accent-gold-dark);
  background: var(--accent-gold-light);
  border: 1px solid var(--accent-gold);
  padding: 2px 8px;
  border-radius: 4px;
  margin-bottom: 6px;
}

.analytics-header-titles h2,
.review-header-left h3 {
  font-family: var(--font-serif-zh);
  color: var(--primary-dark);
  font-size: 1.5rem;
  font-weight: 800;
  margin: 0 0 4px 0;
}

.analytics-header-titles p {
  color: var(--text-muted);
  font-size: 0.88rem;
  margin: 0;
}

/* Metric Cards Grid */
.analytics-stats-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 16px;
  margin-bottom: 26px;
}

.stat-card {
  display: flex;
  align-items: center;
  gap: 14px;
  padding: 16px;
  background: var(--bg-sidebar);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-sm);
  border-left: 4px solid var(--primary);
}

.stat-icon {
  font-size: 2rem;
  line-height: 1;
}

.stat-info {
  display: flex;
  flex-direction: column;
}

.stat-num {
  font-size: 1.6rem;
  font-weight: 800;
  color: var(--primary-dark);
  line-height: 1.1;
  font-family: var(--font-sans);
}

.stat-label {
  font-size: 0.78rem;
  color: var(--text-muted);
  font-weight: 600;
  margin-top: 2px;
}

/* Analytics Section & Table */
.analytics-section {
  background: var(--bg-sidebar);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: 20px;
}

.analytics-section-title {
  display: flex;
  align-items: center;
  justify-content: space-between;
  font-size: 1.05rem;
  font-weight: 800;
  color: var(--primary-dark);
  font-family: var(--font-serif-zh);
  border-bottom: 1px dashed var(--accent-gold);
  padding-bottom: 10px;
  margin-bottom: 16px;
}

.analytics-badge-count {
  font-size: 0.8rem;
  font-weight: 600;
  background: var(--accent-gold-light);
  color: var(--accent-gold-dark);
  border: 1px solid var(--accent-gold);
  padding: 2px 8px;
  border-radius: 12px;
  font-family: var(--font-sans);
}

.analytics-table-wrap {
  overflow-x: auto;
}

.analytics-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.88rem;
}

.analytics-table th {
  text-align: left;
  padding: 10px 12px;
  background: rgba(140, 29, 24, 0.05);
  color: var(--primary);
  font-weight: 700;
  border-bottom: 1.5px solid var(--border-color);
  white-space: nowrap;
}

.analytics-table td {
  padding: 12px;
  border-bottom: 1px solid var(--border-color);
  vertical-align: middle;
}

.analytics-table tr:hover td {
  background: rgba(197, 160, 89, 0.06);
}

.badge-score-pill {
  display: inline-block;
  padding: 3px 8px;
  border-radius: 4px;
  font-weight: 700;
  font-size: 0.82rem;
}

.badge-score-pill.pass {
  background: rgba(46, 117, 89, 0.12);
  color: #2E7559;
  border: 1px solid #3A8E6E;
}

.badge-score-pill.fail {
  background: rgba(140, 29, 24, 0.1);
  color: #8C1D18;
  border: 1px solid #8C1D18;
}

.analytics-starred-chips {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

.starred-chip {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 6px 12px;
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-sm);
  font-size: 0.84rem;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.2s;
}

.starred-chip:hover {
  border-color: var(--primary);
  background: rgba(140, 29, 24, 0.04);
}

.btn-text-action {
  background: none;
  border: none;
  color: var(--primary);
  font-weight: 700;
  font-size: 0.84rem;
  cursor: pointer;
}

.btn-text-action:hover {
  text-decoration: underline;
}

/* ==========================================================================
   QUIZ REVIEW MODAL
   ========================================================================== */
.review-filter-bar {
  display: flex;
  align-items: center;
  gap: 12px;
  margin-bottom: 20px;
  padding: 10px 14px;
  background: var(--bg-sidebar);
  border-radius: var(--radius-md);
  border: 1px solid var(--border-color);
}

.review-filter-bar label {
  font-weight: 700;
  font-size: 0.86rem;
  color: var(--text-muted);
}

.review-filter-pills {
  display: flex;
  gap: 8px;
  flex-wrap: wrap;
}

.rf-pill {
  padding: 5px 12px;
  border: 1px solid var(--border-color);
  background: var(--bg-card);
  color: var(--text-main);
  border-radius: var(--radius-sm);
  font-size: 0.82rem;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.2s;
}

.rf-pill:hover {
  border-color: var(--accent-gold);
}

.rf-pill.active {
  background: var(--primary);
  color: #FFFFFF;
  border-color: var(--primary-dark);
}

.review-questions-list {
  display: flex;
  flex-direction: column;
  gap: 20px;
}

.review-q-card {
  background: var(--bg-sidebar);
  border: 1.5px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: 20px;
  box-shadow: var(--shadow-sm);
}

.review-q-card.q-correct {
  border-left: 5px solid #2E7559;
}

.review-q-card.q-wrong {
  border-left: 5px solid #8C1D18;
}

.review-q-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 12px;
}

.review-q-status-badge {
  font-size: 0.82rem;
  font-weight: 700;
  padding: 3px 8px;
  border-radius: 4px;
}

.review-q-status-badge.correct {
  background: rgba(46, 117, 89, 0.12);
  color: #2E7559;
  border: 1px solid #3A8E6E;
}

.review-q-status-badge.wrong {
  background: rgba(140, 29, 24, 0.1);
  color: #8C1D18;
  border: 1px solid #8C1D18;
}

.review-q-title-zh {
  font-family: var(--font-serif-zh);
  font-size: 1.12rem;
  font-weight: 700;
  color: var(--text-main);
  margin-bottom: 6px;
  line-height: 1.4;
}

.review-q-title-th {
  font-size: 0.9rem;
  color: var(--text-muted);
  margin-bottom: 16px;
  line-height: 1.4;
}

.review-opts-grid {
  display: flex;
  flex-direction: column;
  gap: 8px;
  margin-bottom: 16px;
}

.review-opt-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 10px 14px;
  border-radius: var(--radius-sm);
  border: 1px solid var(--border-color);
  background: var(--bg-card);
  font-size: 0.9rem;
  font-weight: 500;
}

.review-opt-row.opt-user-wrong {
  border-color: #8C1D18;
  background: rgba(140, 29, 24, 0.08);
  color: #8C1D18;
  font-weight: 700;
}

.review-opt-row.opt-correct-target {
  border-color: #2E7559;
  background: rgba(46, 117, 89, 0.08);
  color: #2E7559;
  font-weight: 700;
}

.review-q-explanation {
  background: rgba(197, 160, 89, 0.08);
  border-left: 3px solid var(--accent-gold);
  padding: 12px 16px;
  border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
  font-size: 0.88rem;
}

.review-q-explanation h5 {
  margin: 0 0 4px 0;
  color: var(--primary-dark);
  font-weight: 800;
}

@media (max-width: 768px) {
  .analytics-stats-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  .analytics-modal-dialog,
  .review-modal-dialog {
    padding: 20px 16px;
  }
}

/* ==========================================================================
   Subject Switcher (学科切换器)
   ========================================================================== */
.subject-switcher {
  margin: 10px 14px 14px 14px;
  padding: 10px 12px;
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-sm);
  display: flex;
  align-items: center;
  gap: 8px;
}

.subject-switcher-title {
  font-size: 0.76rem;
  font-weight: 700;
  color: var(--text-light);
  letter-spacing: 0.3px;
  white-space: nowrap;
  flex-shrink: 0;
}

.subject-dropdown {
  flex: 1;
  padding: 7px 12px;
  background: var(--bg-elevated);
  border: 1.5px solid var(--border-color);
  border-radius: var(--radius-sm);
  color: var(--text-main);
  font-size: 0.88rem;
  font-weight: 700;
  font-family: var(--font-sans);
  cursor: pointer;
  outline: none;
  transition: border-color 0.2s, box-shadow 0.2s;
  appearance: auto;
}

.subject-dropdown:focus {
  border-color: var(--accent-gold);
  box-shadow: 0 0 0 2px rgba(197, 160, 89, 0.2);
}

[data-theme="dark"] .subject-dropdown {
  background: #1e1b18;
  color: var(--accent-gold);
  border-color: rgba(229, 193, 88, 0.3);
}

/* ==========================================================================
   Zhongji Reader & Chapters (章节研读)
   ========================================================================== */
.zhongji-banner {
  border-left: 4px solid var(--accent-gold);
  background: linear-gradient(135deg, rgba(197, 160, 89, 0.08) 0%, rgba(140, 29, 24, 0.04) 100%);
}

.zj-chapter-card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  margin-bottom: 20px;
  overflow: hidden;
  box-shadow: var(--shadow-sm);
  transition: box-shadow 0.2s ease, border-color 0.2s ease;
}

.zj-chapter-card:hover {
  border-color: var(--accent-gold);
  box-shadow: var(--shadow-md);
}

.zj-chapter-header {
  padding: 16px 20px;
  background: var(--bg-elevated);
  border-bottom: 1px solid var(--border-color);
  display: flex;
  align-items: center;
  justify-content: space-between;
  cursor: pointer;
  user-select: none;
}

.zj-ch-title-wrap {
  display: flex;
  align-items: baseline;
  gap: 12px;
  flex-wrap: wrap;
}

.zj-ch-title-zh {
  font-size: 1.25rem;
  font-family: var(--font-serif-zh);
  font-weight: 800;
  color: var(--primary);
}

[data-theme="dark"] .zj-ch-title-zh {
  color: var(--accent-gold);
}

.zj-ch-title-th {
  font-size: 0.95rem;
  font-weight: 600;
  color: var(--text-muted);
}

.zj-ch-meta-badge {
  display: inline-flex;
  align-items: center;
  gap: 4px;
  font-size: 0.78rem;
  font-weight: 700;
  padding: 3px 8px;
  border-radius: 9999px;
  background: var(--primary-light);
  color: var(--primary-dark);
}

[data-theme="dark"] .zj-ch-meta-badge {
  background: rgba(229, 193, 88, 0.15);
  color: var(--accent-gold);
}

.zj-chapter-body {
  padding: 20px;
}

.zj-section-block {
  margin-bottom: 24px;
  padding-bottom: 18px;
  border-bottom: 1px dashed var(--border-color);
}

.zj-section-block:last-child {
  margin-bottom: 0;
  padding-bottom: 0;
  border-bottom: none;
}

.zj-section-title-zh {
  font-size: 1.05rem;
  font-weight: 800;
  color: var(--text-main);
  margin-bottom: 4px;
}

.zj-section-title-th {
  font-size: 0.88rem;
  color: var(--text-light);
  margin-bottom: 12px;
}

.zj-keypoints-list {
  list-style: none;
  padding: 0;
  margin: 0;
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.zj-keypoint-item {
  position: relative;
  padding: 8px 14px 8px 30px;
  background: var(--bg-main);
  border-radius: var(--radius-sm);
  font-size: 0.92rem;
  line-height: 1.6;
  border-left: 3px solid var(--accent-gold);
}

.zj-keypoint-item::before {
  content: "✦";
  position: absolute;
  left: 12px;
  top: 9px;
  color: var(--accent-gold);
  font-size: 0.85rem;
}

.zj-raw-toggle-btn {
  margin-top: 14px;
  font-size: 0.82rem;
  font-weight: 700;
  padding: 6px 12px;
  border-radius: var(--radius-sm);
  border: 1px solid var(--border-color);
  background: var(--bg-card);
  color: var(--text-muted);
  cursor: pointer;
  transition: all 0.2s ease;
}

.zj-raw-toggle-btn:hover {
  border-color: var(--accent-gold);
  color: var(--primary);
}

.zj-raw-text-box {
  margin-top: 12px;
  padding: 14px 16px;
  background: var(--bg-elevated);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-sm);
  font-size: 0.86rem;
  line-height: 1.8;
  white-space: pre-wrap;
  color: var(--text-muted);
  max-height: 400px;
  overflow-y: auto;
}

/* ==========================================================================
   Interactive Diagrams (五行生克 & 九种体质)
   ========================================================================== */
.zj-diagrams-subtabs {
  display: flex;
  gap: 8px;
  margin-bottom: 20px;
  flex-wrap: wrap;
}

.zj-subtab-btn {
  padding: 8px 16px;
  border-radius: 9999px;
  border: 1px solid var(--border-color);
  background: var(--bg-card);
  color: var(--text-muted);
  font-size: 0.9rem;
  font-weight: 700;
  cursor: pointer;
  transition: all 0.2s ease;
}

.zj-subtab-btn:hover {
  border-color: var(--accent-gold);
  color: var(--text-main);
}

.zj-subtab-btn.active {
  background: var(--primary);
  color: #FFFFFF;
  border-color: var(--primary);
  box-shadow: 0 2px 6px rgba(140, 29, 24, 0.25);
}

[data-theme="dark"] .zj-subtab-btn.active {
  background: var(--accent-gold);
  color: #171513;
  border-color: var(--accent-gold);
}

/* Five Elements Interactive Section */
.fe-container {
  display: grid;
  grid-template-columns: 1fr 1.2fr;
  gap: 24px;
  align-items: start;
}

@media (max-width: 900px) {
  .fe-container {
    grid-template-columns: 1fr;
  }
}

.fe-wheel-wrap {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: 24px;
  text-align: center;
  box-shadow: var(--shadow-sm);
}

.fe-wheel-title {
  font-size: 1.1rem;
  font-weight: 800;
  margin-bottom: 6px;
  color: var(--primary);
}

[data-theme="dark"] .fe-wheel-title {
  color: var(--accent-gold);
}

.fe-wheel-sub {
  font-size: 0.85rem;
  color: var(--text-light);
  margin-bottom: 20px;
}

.fe-nodes-row {
  display: flex;
  justify-content: center;
  gap: 12px;
  flex-wrap: wrap;
  margin-bottom: 20px;
}

.fe-node-btn {
  width: 60px;
  height: 60px;
  border-radius: 50%;
  border: 3px solid transparent;
  font-size: 1.25rem;
  font-weight: 900;
  color: #FFFFFF;
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  box-shadow: var(--shadow-md);
  transition: transform 0.2s cubic-bezier(0.16, 1, 0.3, 1), box-shadow 0.2s ease;
}

.fe-node-btn:hover {
  transform: scale(1.12);
}

.fe-node-btn.active {
  transform: scale(1.18);
  border-color: #FFFFFF;
  outline: 3px solid var(--accent-gold);
}

.fe-rules-box {
  background: var(--bg-main);
  padding: 14px 16px;
  border-radius: var(--radius-sm);
  font-size: 0.88rem;
  text-align: left;
  line-height: 1.6;
}

.fe-details-card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: 24px;
  box-shadow: var(--shadow-sm);
}

.fe-details-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 16px;
  padding-bottom: 12px;
  border-bottom: 2px solid var(--border-color);
}

.fe-det-title {
  font-size: 1.4rem;
  font-family: var(--font-serif-zh);
  font-weight: 900;
}

.fe-grid-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.9rem;
}

.fe-grid-table th {
  text-align: left;
  padding: 8px 10px;
  background: var(--bg-main);
  color: var(--text-light);
  font-size: 0.8rem;
  font-weight: 700;
  border-bottom: 1px solid var(--border-color);
  width: 35%;
}

.fe-grid-table td {
  padding: 8px 10px;
  border-bottom: 1px solid var(--border-color);
  font-weight: 600;
}

/* 9 Constitutions Grid */
.constitutions-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(320px, 1fr));
  gap: 18px;
}

.const-card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: 18px;
  box-shadow: var(--shadow-sm);
  display: flex;
  flex-direction: column;
  transition: transform 0.2s ease, border-color 0.2s ease;
}

.const-card:hover {
  transform: translateY(-2px);
  border-color: var(--accent-gold);
  box-shadow: var(--shadow-md);
}

.const-card-header {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  margin-bottom: 10px;
  padding-bottom: 8px;
  border-bottom: 1px solid var(--border-color);
}

.const-name-zh {
  font-size: 1.15rem;
  font-family: var(--font-serif-zh);
  font-weight: 800;
  color: var(--primary);
}

[data-theme="dark"] .const-name-zh {
  color: var(--accent-gold);
}

.const-name-th {
  font-size: 0.85rem;
  color: var(--text-light);
  font-weight: 600;
}

.const-row {
  margin-bottom: 8px;
  font-size: 0.86rem;
  line-height: 1.5;
}

.const-label {
  font-weight: 800;
  color: var(--text-muted);
}

[data-theme="dark"] .brand-logo-img,
[data-theme="dark"] .auth-seal-logo,
[data-theme="dark"] .analytics-seal-logo {
  box-shadow: 0 0 14px rgba(229, 193, 88, 0.28);
  border-color: var(--accent-gold);
}

/* ==========================================================================
   MOBILE & TABLET RESPONSIVE ENHANCEMENTS (ข้อ 10)
   ========================================================================== */
@media (max-width: 768px) {
  .top-header {
    flex-wrap: wrap;
    gap: 10px;
    padding: 10px 14px;
  }
  .search-bar {
    order: 3;
    width: 100%;
    max-width: 100%;
  }
  .header-actions {
    margin-left: auto;
    gap: 8px;
  }
  .brand-title {
    font-size: 1.1rem;
  }
  .section-banner {
    padding: 18px 16px;
  }
  .section-banner h1 {
    font-size: 1.35rem;
  }
  .quiz-card {
    padding: 18px 14px;
  }
  .quiz-opt-btn {
    padding: 12px 14px;
    font-size: 0.95rem;
  }
  .exam-modal-dialog,
  .auth-modal-dialog,
  .analytics-modal-dialog,
  .review-modal-dialog {
    width: 94vw !important;
    max-width: 94vw !important;
    margin: 12px auto !important;
    padding: 20px 16px !important;
  }
  .gen-pill-group {
    gap: 6px;
  }
  .gen-pill {
    font-size: 0.8rem;
    padding: 6px 12px;
  }
  .flashcard {
    min-height: 220px;
  }
  .constitutions-grid {
    grid-template-columns: 1fr;
  }
  .analytics-stats-grid {
    grid-template-columns: repeat(2, 1fr);
    gap: 10px;
  }
}

@media (max-width: 480px) {
  .analytics-stats-grid {
    grid-template-columns: 1fr;
  }
  .score-circle {
    width: 90px;
    height: 90px;
    font-size: 1.5rem;
  }
  .quiz-controls-actions {
    flex-direction: column;
    width: 100%;
  }
  .btn-custom-exam,
  .btn-history-exam {
    width: 100%;
    justify-content: center;
  }
}