/* ============================================================
   中文韵 · 全局样式系统
   Chinese Vibes · Global Design System
   ============================================================ */

@import url('https://fonts.googleapis.com/css2?family=Noto+Serif+SC:wght@400;600;700&family=Noto+Sans+SC:wght@300;400;500;700&display=swap');

/* ─── 色彩系统（丝绸之路配色）─── */
:root {
  /* 主色：丝绸金 */
  --gold:        #C8973A;
  --gold-light:  #E8C06A;
  --gold-dark:   #9A6F1E;
  --gold-glow:   rgba(200,151,58,0.25);

  /* 辅色：玉石绿 */
  --jade:        #3D7A5E;
  --jade-light:  #5BA882;
  --jade-pale:   #EAF5EF;

  /* 辅色：沙漠红 */
  --crimson:     #B83A2E;
  --crimson-light:#E05A4C;
  --crimson-pale: #FDF0EF;

  /* 辅色：天青蓝（沙漠夜空） */
  --lapis:       #2A4A7F;
  --lapis-light: #4A72B8;
  --lapis-pale:  #EEF3FC;

  /* 中性色：卡其色（更明亮） */
  --sand-50:     #FDFAF4;
  --sand-100:    #F5EDD8;
  --sand-200:    #E8D9B5;
  --sand-300:    #D4C4A8;
  --sand-400:    #C3B395;

  /* 文字 */
  --text-primary:   #2C1A06;
  --text-secondary: #6B4F2A;
  --text-muted:     #A08050;
  --text-light:     #C8A96E;

  /* 背景 */
  --bg-page:     #FDFAF4;
  --bg-card:     #FFFFFF;
  --bg-sidebar:  #2C1A06;

  /* 边框 */
  --border:      #E8D9B5;
  --border-gold: rgba(200,151,58,0.4);

  /* 阴影 */
  --shadow-sm:   0 2px 8px rgba(44,26,6,0.08);
  --shadow-md:   0 4px 20px rgba(44,26,6,0.12);
  --shadow-lg:   0 8px 40px rgba(44,26,6,0.16);
  --shadow-gold: 0 4px 20px rgba(200,151,58,0.3);

  /* 间距 */
  --radius-sm:   8px;
  --radius-md:   12px;
  --radius-lg:   20px;
  --radius-xl:   28px;

  /* 字体 */
  --font-serif:  'Noto Serif SC', 'STSong', 'SimSun', serif;
  --font-sans:   'Noto Sans SC', 'PingFang SC', 'Microsoft YaHei', sans-serif;
}

/* ─── 全局重置 ─── */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

html { font-size: 16px; scroll-behavior: smooth; }

body {
  font-family: var(--font-sans);
  background: var(--bg-page);
  color: var(--text-primary);
  line-height: 1.6;
  min-height: 100vh;
}

/* ─── 丝路装饰纹样背景 ─── */
.silk-bg {
  background-color: var(--bg-page);
  background-image:
    radial-gradient(circle at 20% 50%, rgba(200,151,58,0.04) 0%, transparent 50%),
    radial-gradient(circle at 80% 20%, rgba(61,122,94,0.04) 0%, transparent 50%),
    url("data:image/svg+xml,%3Csvg width='60' height='60' viewBox='0 0 60 60' xmlns='http://www.w3.org/2000/svg'%3E%3Cg fill='none' fill-rule='evenodd'%3E%3Cg fill='%23C8973A' fill-opacity='0.03'%3E%3Cpath d='M30 30 L36 24 L42 30 L36 36 Z'/%3E%3Cpath d='M0 0 L6 0 L6 6 L0 6 Z'/%3E%3Cpath d='M54 54 L60 54 L60 60 L54 60 Z'/%3E%3C/g%3E%3C/g%3E%3C/svg%3E");
}

/* ─── 导航栏 ─── */
.navbar {
  background: linear-gradient(135deg, #2C1A06 0%, #4A2E0A 50%, #2C1A06 100%);
  border-bottom: 2px solid var(--gold);
  position: sticky;
  top: 0;
  z-index: 1000;
  box-shadow: 0 2px 20px rgba(0,0,0,0.3);
}

.navbar-inner {
  max-width: 1400px;
  margin: 0 auto;
  padding: 0 24px;
  height: 68px;
  display: flex;
  align-items: center;
  gap: 32px;
}

.navbar-brand {
  display: flex;
  align-items: center;
  gap: 12px;
  text-decoration: none;
  flex-shrink: 0;
}

.brand-emblem {
  width: 44px;
  height: 44px;
  background: linear-gradient(135deg, var(--gold) 0%, var(--gold-dark) 100%);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  box-shadow: 0 0 12px var(--gold-glow);
  overflow: hidden;
}

/* 卷曲环图标 */
.brand-emblem svg {
  width: 32px;
  height: 32px;
}

.brand-icon {
  font-size: 24px;
  line-height: 1;
}

.brand-text { line-height: 1.2; }
.brand-zh {
  font-family: var(--font-serif);
  font-size: 15px;
  font-weight: 700;
  color: var(--gold-light);
  letter-spacing: 2px;
}
.brand-en {
  font-size: 10px;
  color: var(--sand-300);
  letter-spacing: 1px;
  text-transform: uppercase;
}

.navbar-nav {
  display: flex;
  align-items: center;
  gap: 4px;
  flex: 1;
  list-style: none;
}

.nav-link {
  display: flex;
  align-items: center;
  gap: 6px;
  padding: 8px 14px;
  border-radius: var(--radius-sm);
  text-decoration: none;
  color: var(--sand-200);
  font-size: 13px;
  font-weight: 500;
  transition: all 0.2s;
  white-space: nowrap;
}
.nav-link:hover, .nav-link.active {
  background: rgba(200,151,58,0.2);
  color: var(--gold-light);
}
.nav-link .nav-icon { font-size: 15px; }

.navbar-right {
  display: flex;
  align-items: center;
  gap: 12px;
  margin-left: auto;
}

.user-badge {
  display: flex;
  align-items: center;
  gap: 8px;
  background: rgba(200,151,58,0.15);
  border: 1px solid var(--border-gold);
  border-radius: 24px;
  padding: 6px 14px;
  cursor: pointer;
  transition: all 0.2s;
}
.user-badge:hover { background: rgba(200,151,58,0.25); }
.user-avatar {
  width: 28px; height: 28px;
  background: linear-gradient(135deg, var(--gold), var(--gold-dark));
  border-radius: 50%;
  display: flex; align-items: center; justify-content: center;
  font-size: 14px;
}
.user-name { color: var(--sand-100); font-size: 13px; font-weight: 500; }
.user-points { color: var(--gold-light); font-size: 12px; }

/* ─── 导航余额徽章 ─── */
.nav-balance-badge {
  display: flex;
  align-items: center;
  gap: 5px;
  padding: 4px 10px;
  border-radius: 20px;
  border: 1px solid rgba(91,168,130,0.45);
  background: rgba(91,168,130,0.12);
  font-size: 11px;
  color: var(--jade-light);
  white-space: nowrap;
  cursor: pointer;
  transition: all 0.2s;
}
.nav-balance-badge:hover { background: rgba(91,168,130,0.22); }
.nav-balance-badge .nb-label { font-size: 10px; color: rgba(255,255,255,0.45); }
.nav-balance-badge .nb-amount { font-weight: 700; font-size: 12px; color: var(--jade-light); }

/* 低余额状态（≤200 AED）→ 红色警示 */
.nav-balance-badge.low-balance {
  border-color: rgba(184,58,46,0.7);
  background: rgba(184,58,46,0.18);
  animation: balancePulse 2s infinite;
}
.nav-balance-badge.low-balance .nb-amount { color: #FF6B6B; }
.nav-balance-badge.low-balance .nb-label { color: rgba(255,150,150,0.7); }

@keyframes balancePulse {
  0%, 100% { box-shadow: 0 0 0 0 rgba(184,58,46,0.35); }
  50%       { box-shadow: 0 0 0 5px rgba(184,58,46,0); }
}

/* 低余额续费提醒条（页面顶部） */
.low-balance-alert {
  background: linear-gradient(90deg, #8B1E18, #B83A2E, #8B1E18);
  color: #fff;
  padding: 9px 24px;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 12px;
  font-size: 13px;
  font-weight: 600;
  position: sticky;
  top: 0;
  z-index: 999;
  animation: alertShake 0.5s ease;
}
.low-balance-alert a {
  background: #fff;
  color: #B83A2E;
  border-radius: 99px;
  padding: 3px 14px;
  font-size: 12px;
  font-weight: 700;
  text-decoration: none;
  white-space: nowrap;
}
.low-balance-alert a:hover { background: #FFE5E2; }
@keyframes alertShake {
  0%,100% { transform: translateX(0); }
  20%      { transform: translateX(-4px); }
  40%      { transform: translateX(4px); }
  60%      { transform: translateX(-2px); }
  80%      { transform: translateX(2px); }
}

/* ─── 语言切换器 ─── */
.lang-switcher {
  display: flex;
  align-items: center;
  gap: 6px;
  padding: 6px 12px;
  border-radius: 20px;
  border: 1px solid rgba(200,151,58,0.3);
  cursor: pointer;
  transition: all 0.2s;
  position: relative;
  background: rgba(200,151,58,0.1);
  white-space: nowrap;
}
.lang-switcher:hover { background: rgba(200,151,58,0.2); border-color: var(--gold); }

.lang-dropdown {
  position: absolute;
  top: calc(100% + 8px);
  right: 0;
  background: #fff;
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-lg);
  z-index: 2000;
  min-width: 160px;
  overflow: hidden;
  animation: fadeIn 0.15s ease;
}

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

@keyframes slideUp {
  from { opacity: 0; transform: translateX(-50%) translateY(30px); }
  to   { opacity: 1; transform: translateX(-50%) translateY(0); }
}

.lang-option {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 10px 16px;
  cursor: pointer;
  font-size: 13px;
  color: var(--text-primary);
  transition: background 0.1s;
}
.lang-option:hover { background: var(--sand-50); }
.lang-option.active {
  background: var(--gold-glow);
  color: var(--gold-dark);
  font-weight: 700;
}

/* ─── 角色标签 ─── */
.role-badge-teacher   { background: linear-gradient(135deg, #2A5A3E, #3D7A5E); color: #fff; }
.role-badge-companion { background: linear-gradient(135deg, #2A4A7F, #4A72B8); color: #fff; }
.role-badge-admin     { background: linear-gradient(135deg, #8B7355, #A08060); color: #fff; }
.role-badge-student   { background: linear-gradient(135deg, #B83A2E, #E05A4C); color: #fff; }

/* ─── 语伴状态指示灯 ─── */
.status-dot {
  width: 9px; height: 9px;
  border-radius: 50%;
  display: inline-block;
  flex-shrink: 0;
}
.status-dot.online  { background: #4CAF50; box-shadow: 0 0 6px rgba(76,175,80,0.6); animation: pulse-green 2s infinite; }
.status-dot.busy    { background: #FF9800; box-shadow: 0 0 6px rgba(255,152,0,0.6); }
.status-dot.offline { background: #9E9E9E; }

@keyframes pulse-green {
  0%, 100% { box-shadow: 0 0 4px rgba(76,175,80,0.4); }
  50%       { box-shadow: 0 0 10px rgba(76,175,80,0.8); }
}

/* ─── 语伴卡片 ─── */
.companion-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 20px;
  box-shadow: var(--shadow-sm);
  transition: all 0.2s;
  position: relative;
  overflow: hidden;
}
.companion-card::before {
  content: '';
  position: absolute;
  top: 0; left: 0; right: 0;
  height: 3px;
  background: linear-gradient(90deg, var(--lapis), var(--lapis-light), var(--gold));
}
.companion-card:hover {
  box-shadow: var(--shadow-md);
  transform: translateY(-2px);
  border-color: var(--lapis-light);
}

.companion-avatar-wrap {
  width: 60px; height: 60px;
  border-radius: 50%;
  display: flex; align-items: center; justify-content: center;
  font-size: 28px;
  background: linear-gradient(135deg, var(--lapis), var(--lapis-light));
  box-shadow: 0 4px 12px rgba(42,74,127,0.25);
  flex-shrink: 0;
  position: relative;
}
.companion-avatar-wrap .status-dot {
  position: absolute;
  bottom: 2px; right: 2px;
  width: 12px; height: 12px;
  border: 2px solid #fff;
}

/* ─── 计时器 ─── */
.session-timer {
  font-family: var(--font-serif);
  font-size: 48px;
  font-weight: 700;
  color: var(--gold-light);
  text-align: center;
  letter-spacing: 4px;
  text-shadow: 0 0 20px var(--gold-glow);
}

/* ─── 进度条（语伴奖励） ─── */
.progress-bar-wrap {
  background: var(--sand-100);
  border-radius: 99px;
  height: 10px;
  overflow: hidden;
}
.progress-bar-fill {
  height: 100%;
  border-radius: 99px;
  background: linear-gradient(90deg, var(--lapis), var(--gold));
  transition: width 0.6s ease;
}

/* ─── 页面布局 ─── */
.page-layout {
  max-width: 1400px;
  margin: 0 auto;
  padding: 28px 24px;
}

.page-header {
  margin-bottom: 28px;
}

.page-title {
  font-family: var(--font-serif);
  font-size: 26px;
  color: var(--text-primary);
  font-weight: 700;
}
.page-title span { color: var(--gold-dark); }

.page-subtitle {
  font-size: 14px;
  color: var(--text-muted);
  margin-top: 4px;
}

/* ─── 卡片系统 ─── */
.card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 24px;
  box-shadow: var(--shadow-sm);
  transition: box-shadow 0.2s;
}
.card:hover { box-shadow: var(--shadow-md); }

.card-gold {
  background: linear-gradient(135deg, #FDF8EE 0%, #F5EDD8 100%);
  border: 1px solid var(--border-gold);
}

.card-dark {
  background: linear-gradient(135deg, #2C1A06 0%, #4A2E0A 100%);
  border: 1px solid rgba(200,151,58,0.3);
  color: var(--sand-100);
}

.card-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 20px;
}

.card-title {
  font-family: var(--font-serif);
  font-size: 16px;
  font-weight: 700;
  color: var(--text-primary);
  display: flex;
  align-items: center;
  gap: 8px;
}
.card-title .icon { font-size: 18px; }
.card-dark .card-title { color: var(--gold-light); }

/* ─── 统计数字卡片 ─── */
.stat-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  padding: 20px;
  text-align: center;
  position: relative;
  overflow: hidden;
  transition: all 0.25s;
}
.stat-card::before {
  content: '';
  position: absolute;
  top: 0; left: 0; right: 0;
  height: 3px;
}
.stat-card.gold::before { background: linear-gradient(90deg, var(--gold), var(--gold-light)); }
.stat-card.jade::before { background: linear-gradient(90deg, var(--jade), var(--jade-light)); }
.stat-card.crimson::before { background: linear-gradient(90deg, var(--crimson), var(--crimson-light)); }
.stat-card.lapis::before { background: linear-gradient(90deg, var(--lapis), var(--lapis-light)); }

.stat-card:hover { transform: translateY(-2px); box-shadow: var(--shadow-md); }

.stat-value {
  font-family: var(--font-serif);
  font-size: 32px;
  font-weight: 700;
  color: var(--text-primary);
  line-height: 1;
}
.stat-label { font-size: 12px; color: var(--text-muted); margin-top: 6px; }
.stat-change { font-size: 11px; margin-top: 4px; }
.stat-change.up { color: var(--jade); }
.stat-change.down { color: var(--crimson); }

/* ─── 按钮系统 ─── */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 10px 20px;
  border-radius: var(--radius-md);
  font-size: 14px;
  font-weight: 600;
  font-family: var(--font-sans);
  cursor: pointer;
  border: none;
  transition: all 0.2s;
  text-decoration: none;
  white-space: nowrap;
}

.btn-gold {
  background: linear-gradient(135deg, var(--gold) 0%, var(--gold-dark) 100%);
  color: #fff;
  box-shadow: 0 2px 12px var(--gold-glow);
}
.btn-gold:hover {
  transform: translateY(-1px);
  box-shadow: 0 4px 20px var(--gold-glow);
}

.btn-jade {
  background: linear-gradient(135deg, var(--jade) 0%, #2A5A44 100%);
  color: #fff;
}
.btn-jade:hover { transform: translateY(-1px); box-shadow: 0 4px 16px rgba(61,122,94,0.3); }

.btn-outline {
  background: transparent;
  color: var(--gold-dark);
  border: 1.5px solid var(--gold);
}
.btn-outline:hover { background: var(--gold-glow); }

.btn-sm { padding: 6px 14px; font-size: 12px; }
.btn-lg { padding: 14px 28px; font-size: 16px; }

/* ─── 进度条 ─── */
.progress-bar-wrap {
  background: var(--sand-100);
  border-radius: 99px;
  overflow: hidden;
  height: 8px;
}
.progress-bar-fill {
  height: 100%;
  border-radius: 99px;
  background: linear-gradient(90deg, var(--gold) 0%, var(--gold-light) 100%);
  transition: width 0.6s ease;
}
.progress-bar-fill.jade {
  background: linear-gradient(90deg, var(--jade) 0%, var(--jade-light) 100%);
}
.progress-bar-fill.lapis {
  background: linear-gradient(90deg, var(--lapis) 0%, var(--lapis-light) 100%);
}

/* ─── 徽章 ─── */
.badge {
  display: inline-flex;
  align-items: center;
  gap: 4px;
  padding: 3px 10px;
  border-radius: 99px;
  font-size: 11px;
  font-weight: 600;
}
.badge-gold { background: #FEF3D0; color: var(--gold-dark); border: 1px solid var(--gold-light); }
.badge-jade { background: var(--jade-pale); color: var(--jade); border: 1px solid #A8D5BC; }
.badge-crimson { background: var(--crimson-pale); color: var(--crimson); border: 1px solid #F0B0A8; }
.badge-lapis { background: var(--lapis-pale); color: var(--lapis); border: 1px solid #B0C4E8; }

/* ─── 分隔线（丝绸装饰） ─── */
.silk-divider {
  position: relative;
  text-align: center;
  margin: 24px 0;
}
.silk-divider::before {
  content: '';
  position: absolute;
  top: 50%;
  left: 0; right: 0;
  height: 1px;
  background: linear-gradient(90deg, transparent, var(--gold-light), transparent);
}
.silk-divider span {
  position: relative;
  background: var(--bg-page);
  padding: 0 12px;
  color: var(--gold);
  font-size: 16px;
}

/* ─── 丝路横幅装饰 ─── */
.silk-banner {
  background: linear-gradient(135deg, #2C1A06 0%, #5A3410 50%, #2C1A06 100%);
  border: 1px solid rgba(200,151,58,0.4);
  border-radius: var(--radius-lg);
  padding: 28px 32px;
  color: var(--sand-100);
  position: relative;
  overflow: hidden;
}
.silk-banner::before {
  content: '🌙✦◆✦🌙';
  position: absolute;
  top: -8px;
  right: 24px;
  font-size: 28px;
  opacity: 0.3;
  letter-spacing: 8px;
}
.silk-banner::after {
  content: '';
  position: absolute;
  bottom: 0; left: 0; right: 0;
  height: 3px;
  background: linear-gradient(90deg, transparent, var(--gold), var(--gold-light), var(--gold), transparent);
}

/* ─── 网格布局 ─── */
.grid-2 { display: grid; grid-template-columns: repeat(2, 1fr); gap: 20px; }
.grid-3 { display: grid; grid-template-columns: repeat(3, 1fr); gap: 20px; }
.grid-4 { display: grid; grid-template-columns: repeat(4, 1fr); gap: 16px; }
.grid-auto { display: grid; grid-template-columns: repeat(auto-fill, minmax(240px, 1fr)); gap: 20px; }

@media (max-width: 1100px) {
  .grid-4 { grid-template-columns: repeat(2, 1fr); }
}
@media (max-width: 768px) {
  .grid-2, .grid-3, .grid-4 { grid-template-columns: 1fr; }
  .navbar-nav { display: none; }
  .page-layout { padding: 16px; }
}

/* ─── 弹窗 ─── */
.modal-overlay {
  position: fixed; inset: 0;
  background: rgba(44,26,6,0.7);
  backdrop-filter: blur(4px);
  z-index: 9000;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 20px;
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.25s;
}
.modal-overlay.open { opacity: 1; pointer-events: all; }

.modal-box {
  background: var(--bg-card);
  border-radius: var(--radius-xl);
  padding: 32px;
  width: 100%;
  max-width: 500px;
  max-height: 90vh;
  overflow-y: auto;
  box-shadow: 0 20px 60px rgba(0,0,0,0.4);
  transform: scale(0.95) translateY(10px);
  transition: transform 0.25s;
  border-top: 4px solid var(--gold);
}
.modal-overlay.open .modal-box { transform: scale(1) translateY(0); }

.modal-title {
  font-family: var(--font-serif);
  font-size: 20px;
  font-weight: 700;
  color: var(--text-primary);
  margin-bottom: 20px;
  padding-bottom: 12px;
  border-bottom: 1px solid var(--border);
}

/* ─── 表单控件 ─── */
.form-group { margin-bottom: 16px; }
.form-label { display: block; font-size: 13px; font-weight: 600; color: var(--text-secondary); margin-bottom: 6px; }
.form-input {
  width: 100%;
  padding: 10px 14px;
  border: 1.5px solid var(--border);
  border-radius: var(--radius-sm);
  font-size: 14px;
  font-family: var(--font-sans);
  color: var(--text-primary);
  background: var(--bg-page);
  transition: border-color 0.2s;
  outline: none;
}
.form-input:focus { border-color: var(--gold); box-shadow: 0 0 0 3px var(--gold-glow); }

.form-select {
  width: 100%;
  padding: 10px 14px;
  border: 1.5px solid var(--border);
  border-radius: var(--radius-sm);
  font-size: 14px;
  font-family: var(--font-sans);
  color: var(--text-primary);
  background: var(--bg-page);
  cursor: pointer;
  outline: none;
}
.form-select:focus { border-color: var(--gold); }

/* ─── 通知提示 ─── */
.toast {
  position: fixed;
  bottom: 24px;
  right: 24px;
  background: #2C1A06;
  color: var(--sand-100);
  padding: 14px 20px;
  border-radius: var(--radius-md);
  border-left: 4px solid var(--gold);
  font-size: 14px;
  z-index: 9999;
  box-shadow: var(--shadow-lg);
  transform: translateX(120%);
  transition: transform 0.3s;
  max-width: 320px;
}
.toast.show { transform: translateX(0); }

/* ─── 积分显示 ─── */
.points-display {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  background: linear-gradient(135deg, #FEF3D0, #F5E5A0);
  border: 1px solid var(--gold-light);
  border-radius: 99px;
  padding: 4px 12px;
  font-size: 13px;
  font-weight: 700;
  color: var(--gold-dark);
}

/* ─── 标签页 ─── */
.tabs {
  display: flex;
  gap: 4px;
  background: var(--sand-100);
  border-radius: var(--radius-md);
  padding: 4px;
  margin-bottom: 24px;
}
.tab-btn {
  flex: 1;
  padding: 8px 16px;
  border: none;
  border-radius: var(--radius-sm);
  background: transparent;
  font-size: 13px;
  font-weight: 600;
  color: var(--text-muted);
  cursor: pointer;
  transition: all 0.2s;
}
.tab-btn.active {
  background: var(--bg-card);
  color: var(--gold-dark);
  box-shadow: var(--shadow-sm);
}

/* ─── 滚动条美化 ─── */
::-webkit-scrollbar { width: 6px; height: 6px; }
::-webkit-scrollbar-track { background: var(--sand-100); }
::-webkit-scrollbar-thumb { background: var(--sand-300); border-radius: 99px; }
::-webkit-scrollbar-thumb:hover { background: var(--gold); }

/* ─── 工具类 ─── */
.flex { display: flex; }
.flex-center { display: flex; align-items: center; justify-content: center; }
.flex-between { display: flex; align-items: center; justify-content: space-between; }
.gap-4 { gap: 4px; }
.gap-8 { gap: 8px; }
.gap-12 { gap: 12px; }
.gap-16 { gap: 16px; }
.gap-20 { gap: 20px; }
.mt-8 { margin-top: 8px; }
.mt-12 { margin-top: 12px; }
.mt-16 { margin-top: 16px; }
.mt-20 { margin-top: 20px; }
.mt-24 { margin-top: 24px; }
.mb-8 { margin-bottom: 8px; }
.mb-12 { margin-bottom: 12px; }
.mb-16 { margin-bottom: 16px; }
.mb-20 { margin-bottom: 20px; }
.text-sm { font-size: 12px; }
.text-md { font-size: 14px; }
.text-lg { font-size: 18px; }
.text-xl { font-size: 22px; }
.text-muted { color: var(--text-muted); }
.text-gold { color: var(--gold-dark); }
.text-jade { color: var(--jade); }
.text-crimson { color: var(--crimson); }
.font-serif { font-family: var(--font-serif); }
.font-bold { font-weight: 700; }
.text-center { text-align: center; }
.w-full { width: 100%; }
.rounded { border-radius: var(--radius-md); }

/* ─── 赞助商/商会展示区 ─── */
.sponsor-strip {
  background: var(--sand-50);
  border-top: 1px solid var(--border);
  border-bottom: 1px solid var(--border);
  padding: 12px 0;
  overflow: hidden;
}
.sponsor-track {
  display: flex;
  gap: 40px;
  animation: scrollSponsor 30s linear infinite;
  width: max-content;
}
.sponsor-item {
  display: flex;
  align-items: center;
  gap: 8px;
  white-space: nowrap;
  font-size: 13px;
  color: var(--text-secondary);
  font-weight: 500;
}
.sponsor-item span { font-size: 18px; }

@keyframes scrollSponsor {
  0% { transform: translateX(0); }
  100% { transform: translateX(-50%); }
}

/* ─── 丝路地图装饰线 ─── */
.route-line {
  height: 2px;
  background: linear-gradient(90deg,
    var(--crimson) 0%,
    var(--gold) 25%,
    var(--jade) 50%,
    var(--lapis) 75%,
    var(--gold) 100%);
  border-radius: 99px;
  margin: 20px 0;
}

/* ─── 词汇卡片 ─── */
.vocab-card {
  perspective: 1000px;
  cursor: pointer;
  height: 220px;
}
.vocab-card-inner {
  position: relative;
  width: 100%; height: 100%;
  transition: transform 0.5s;
  transform-style: preserve-3d;
}
.vocab-card.flipped .vocab-card-inner { transform: rotateY(180deg); }
.vocab-card-front, .vocab-card-back {
  position: absolute; inset: 0;
  backface-visibility: hidden;
  border-radius: var(--radius-lg);
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  padding: 20px;
  border: 1.5px solid var(--border);
  box-shadow: var(--shadow-sm);
}
.vocab-card-front {
  background: linear-gradient(135deg, #FDF8EE, #F5EDD8);
}
.vocab-card-back {
  background: linear-gradient(135deg, #2C1A06, #4A2E0A);
  transform: rotateY(180deg);
  color: var(--sand-100);
}
.vocab-emoji { font-size: 52px; margin-bottom: 12px; }
.vocab-char {
  font-family: var(--font-serif);
  font-size: 36px;
  font-weight: 700;
  color: var(--text-primary);
}
.vocab-card-back .vocab-char { color: var(--gold-light); }
.vocab-pinyin { font-size: 16px; color: var(--gold-dark); margin-top: 4px; font-style: italic; }
.vocab-card-back .vocab-pinyin { color: var(--sand-300); }
.vocab-english { font-size: 14px; color: var(--text-muted); margin-top: 6px; }
.vocab-card-back .vocab-english { color: var(--sand-200); }

/* ─── 图表容器 ─── */
.chart-container {
  position: relative;
  width: 100%;
}

/* ─── 骨架屏（加载中） ─── */
.skeleton {
  background: linear-gradient(90deg, var(--sand-100) 25%, var(--sand-200) 50%, var(--sand-100) 75%);
  background-size: 200% 100%;
  animation: shimmer 1.5s infinite;
  border-radius: var(--radius-sm);
}
@keyframes shimmer {
  0% { background-position: 200% 0; }
  100% { background-position: -200% 0; }
}

/* ─── 响应式汉堡菜单 ─── */
.hamburger {
  display: none;
  flex-direction: column;
  gap: 5px;
  cursor: pointer;
  padding: 4px;
}
.hamburger span {
  display: block;
  width: 22px; height: 2px;
  background: var(--sand-200);
  border-radius: 2px;
  transition: all 0.2s;
}
@media (max-width: 768px) {
  .hamburger { display: flex; }
}

/* ─── 页脚 ─── */
.footer {
  background: linear-gradient(135deg, #2C1A06 0%, #1A0E04 100%);
  border-top: 2px solid var(--gold);
  padding: 40px 24px 24px;
  margin-top: 60px;
}
.footer-inner {
  max-width: 1400px;
  margin: 0 auto;
}
.footer-grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1fr;
  gap: 40px;
  margin-bottom: 32px;
}
.footer-brand-desc {
  font-size: 13px;
  color: var(--sand-300);
  line-height: 1.7;
  margin-top: 12px;
}
.footer-heading {
  font-family: var(--font-serif);
  font-size: 13px;
  color: var(--gold-light);
  font-weight: 700;
  letter-spacing: 1px;
  margin-bottom: 12px;
}
.footer-links { list-style: none; }
.footer-links li { margin-bottom: 8px; }
.footer-links a {
  font-size: 13px;
  color: var(--sand-300);
  text-decoration: none;
  transition: color 0.2s;
}
.footer-links a:hover { color: var(--gold-light); }
.footer-bottom {
  padding-top: 20px;
  border-top: 1px solid rgba(200,151,58,0.2);
  display: flex;
  justify-content: space-between;
  align-items: center;
}
.footer-copy { font-size: 12px; color: var(--sand-400); }
.footer-silk { font-size: 12px; color: var(--gold); letter-spacing: 2px; }

@media (max-width: 768px) {
  .footer-grid { grid-template-columns: 1fr 1fr; gap: 24px; }
}

/* ─── 全局浮动会员CTA栏 ─── */
.float-member-bar {
  position: fixed;
  bottom: 0; left: 0; right: 0;
  background: linear-gradient(135deg, #2C1A06 0%, #4A2E0A 50%, #2C1A06 100%);
  border-top: 2px solid var(--gold);
  padding: 10px 24px;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 16px;
  z-index: 9998;
  box-shadow: 0 -4px 24px rgba(0,0,0,0.2);
  transform: translateY(100%);
  transition: transform 0.3s ease;
}
.float-member-bar.show { transform: translateY(0); }
.float-member-bar-text {
  color: var(--sand-200);
  font-size: 13px;
  display: flex;
  align-items: center;
  gap: 8px;
}
.float-member-bar-text strong { color: var(--gold-light); font-weight: 700; }
.float-member-bar-btn {
  background: linear-gradient(135deg, var(--gold), var(--gold-dark));
  color: #fff;
  padding: 8px 20px;
  border-radius: 20px;
  font-size: 14px;
  font-weight: 700;
  text-decoration: none;
  white-space: nowrap;
  transition: all 0.2s;
  border: none;
  cursor: pointer;
}
.float-member-bar-btn:hover {
  transform: translateY(-1px);
  box-shadow: 0 4px 16px rgba(200,151,58,0.5);
}
.float-member-bar-close {
  background: none; border: none;
  color: var(--sand-400);
  font-size: 18px;
  cursor: pointer;
  padding: 0 4px;
  line-height: 1;
}
@media (max-width: 768px) {
  .float-member-bar { padding: 8px 16px; gap: 10px; }
  .float-member-bar-text { font-size: 12px; }
  .float-member-bar-text .hide-mobile { display: none; }
  .float-member-bar-btn { padding: 7px 16px; font-size: 13px; }
}