/* =============================================
   老司机 - 游戏解说社区 | 858386.cn
   主样式文件 | 电竞深蓝+金色+霓虹配色
   ============================================= */

/* ---- CSS变量 ---- */
:root {
  --primary: #0a0e1a;
  --secondary: #0d1b3e;
  --accent: #c9a227;
  --accent2: #e63946;
  --neon-blue: #00d4ff;
  --neon-gold: #ffd700;
  --text-main: #e8eaf0;
  --text-muted: #8a9bb5;
  --card-bg: #111827;
  --card-border: rgba(201,162,39,0.25);
  --gradient-hero: linear-gradient(135deg, #0a0e1a 0%, #0d1b3e 50%, #1a0a2e 100%);
  --gradient-gold: linear-gradient(90deg, #c9a227, #ffd700, #c9a227);
  --gradient-neon: linear-gradient(90deg, #00d4ff, #7b2fff, #e63946);
  --shadow-gold: 0 0 20px rgba(201,162,39,0.4);
  --shadow-neon: 0 0 15px rgba(0,212,255,0.3);
  --radius: 8px;
  --radius-lg: 16px;
  --transition: 0.3s ease;
  --font-main: 'Microsoft YaHei', '微软雅黑', 'PingFang SC', sans-serif;
}

/* ---- 全局重置 ---- */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; font-size: 16px; }
body {
  font-family: var(--font-main);
  background: var(--primary);
  color: var(--text-main);
  line-height: 1.7;
  overflow-x: hidden;
}
a { color: var(--accent); text-decoration: none; transition: color var(--transition); }
a:hover { color: var(--neon-blue); }
img { max-width: 100%; height: auto; display: block; }
ul { list-style: none; }

/* ---- 滚动条 ---- */
::-webkit-scrollbar { width: 6px; }
::-webkit-scrollbar-track { background: var(--primary); }
::-webkit-scrollbar-thumb { background: var(--accent); border-radius: 3px; }

/* ---- 通用容器 ---- */
.container { max-width: 1200px; margin: 0 auto; padding: 0 20px; }
.section { padding: 70px 0; }
.section-alt { background: var(--secondary); }

/* ---- 标题装饰 ---- */
.section-title {
  font-size: 2rem;
  font-weight: 700;
  text-align: center;
  margin-bottom: 12px;
  background: var(--gradient-gold);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  position: relative;
}
.section-subtitle {
  text-align: center;
  color: var(--text-muted);
  margin-bottom: 48px;
  font-size: 0.95rem;
}
.section-title::after {
  content: '';
  display: block;
  width: 60px;
  height: 3px;
  background: var(--gradient-gold);
  margin: 12px auto 0;
  border-radius: 2px;
}

/* ---- 按钮 ---- */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 12px 28px;
  border-radius: var(--radius);
  font-size: 0.95rem;
  font-weight: 600;
  cursor: pointer;
  transition: all var(--transition);
  border: none;
  font-family: var(--font-main);
}
.btn-primary {
  background: var(--gradient-gold);
  color: #0a0e1a;
}
.btn-primary:hover {
  box-shadow: var(--shadow-gold);
  transform: translateY(-2px);
  color: #0a0e1a;
}
.btn-outline {
  background: transparent;
  border: 1.5px solid var(--accent);
  color: var(--accent);
}
.btn-outline:hover {
  background: var(--accent);
  color: #0a0e1a;
  box-shadow: var(--shadow-gold);
}
.btn-neon {
  background: transparent;
  border: 1.5px solid var(--neon-blue);
  color: var(--neon-blue);
}
.btn-neon:hover {
  background: var(--neon-blue);
  color: #0a0e1a;
  box-shadow: var(--shadow-neon);
}

/* ---- 标签 ---- */
.tag {
  display: inline-block;
  padding: 3px 10px;
  border-radius: 20px;
  font-size: 0.75rem;
  font-weight: 600;
  background: rgba(201,162,39,0.15);
  color: var(--accent);
  border: 1px solid rgba(201,162,39,0.3);
}
.tag-red { background: rgba(230,57,70,0.15); color: var(--accent2); border-color: rgba(230,57,70,0.3); }
.tag-blue { background: rgba(0,212,255,0.1); color: var(--neon-blue); border-color: rgba(0,212,255,0.25); }

/* ============================================
   导航栏
   ============================================ */
#navbar {
  position: fixed;
  top: 0; left: 0; right: 0;
  z-index: 1000;
  background: rgba(10,14,26,0.95);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid rgba(201,162,39,0.2);
  transition: all var(--transition);
}
#navbar.scrolled {
  background: rgba(10,14,26,0.98);
  box-shadow: 0 4px 20px rgba(0,0,0,0.5);
}
.nav-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 64px;
  gap: 20px;
}
.nav-brand {
  display: flex;
  align-items: center;
  gap: 10px;
  flex-shrink: 0;
}
.nav-favicon {
  width: 32px;
  height: 32px;
  border-radius: 6px;
  object-fit: cover;
  border: 1px solid rgba(201,162,39,0.4);
}
.nav-logo {
  height: 40px;
  width: auto;
  object-fit: contain;
}
.nav-brand-text {
  font-size: 1.1rem;
  font-weight: 700;
  background: var(--gradient-gold);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  white-space: nowrap;
}
.nav-menu {
  display: flex;
  align-items: center;
  gap: 4px;
}
.nav-menu a {
  padding: 8px 14px;
  border-radius: var(--radius);
  font-size: 0.88rem;
  font-weight: 500;
  color: var(--text-muted);
  white-space: nowrap;
  transition: all var(--transition);
}
.nav-menu a:hover, .nav-menu a.active {
  color: var(--accent);
  background: rgba(201,162,39,0.1);
}
.nav-search {
  display: flex;
  align-items: center;
  background: rgba(255,255,255,0.05);
  border: 1px solid rgba(201,162,39,0.2);
  border-radius: 20px;
  padding: 6px 14px;
  gap: 8px;
  min-width: 180px;
}
.nav-search input {
  background: none;
  border: none;
  outline: none;
  color: var(--text-main);
  font-size: 0.85rem;
  width: 100%;
  font-family: var(--font-main);
}
.nav-search input::placeholder { color: var(--text-muted); }
.nav-search-btn {
  background: none;
  border: none;
  color: var(--accent);
  cursor: pointer;
  font-size: 0.9rem;
  padding: 0;
  display: flex;
  align-items: center;
}
.nav-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  cursor: pointer;
  padding: 4px;
}
.nav-toggle span {
  display: block;
  width: 24px;
  height: 2px;
  background: var(--accent);
  border-radius: 2px;
  transition: all var(--transition);
}

/* ============================================
   搜索栏（导航下方）
   ============================================ */
.search-bar-wrap {
  background: rgba(13,27,62,0.9);
  border-bottom: 1px solid rgba(201,162,39,0.15);
  padding: 10px 0;
}
.search-bar-inner {
  display: flex;
  align-items: center;
  gap: 12px;
  max-width: 700px;
  margin: 0 auto;
  padding: 0 20px;
}
.search-bar-inner input {
  flex: 1;
  background: rgba(255,255,255,0.06);
  border: 1px solid rgba(201,162,39,0.3);
  border-radius: 24px;
  padding: 10px 20px;
  color: var(--text-main);
  font-size: 0.9rem;
  outline: none;
  font-family: var(--font-main);
  transition: border-color var(--transition);
}
.search-bar-inner input:focus { border-color: var(--accent); }
.search-bar-inner button {
  background: var(--gradient-gold);
  border: none;
  border-radius: 24px;
  padding: 10px 24px;
  color: #0a0e1a;
  font-weight: 700;
  cursor: pointer;
  font-size: 0.88rem;
  font-family: var(--font-main);
  transition: all var(--transition);
}
.search-bar-inner button:hover { box-shadow: var(--shadow-gold); }

/* ============================================
   Hero Banner
   ============================================ */
.hero {
  position: relative;
  min-height: 100vh;
  display: flex;
  align-items: center;
  overflow: hidden;
  padding-top: 120px;
}
.hero-bg {
  position: absolute;
  inset: 0;
  background-image: url('../images/hero_banner.jpg');
  background-size: cover;
  background-position: center;
  background-repeat: no-repeat;
  filter: brightness(0.35);
  z-index: 0;
}
.hero-overlay {
  position: absolute;
  inset: 0;
  background: linear-gradient(180deg, rgba(10,14,26,0.3) 0%, rgba(10,14,26,0.7) 60%, rgba(10,14,26,1) 100%);
  z-index: 1;
}
.hero-content {
  position: relative;
  z-index: 2;
  max-width: 800px;
}
.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  background: rgba(201,162,39,0.15);
  border: 1px solid rgba(201,162,39,0.4);
  border-radius: 20px;
  padding: 6px 16px;
  font-size: 0.82rem;
  color: var(--accent);
  margin-bottom: 24px;
}
.hero-badge::before {
  content: '';
  width: 8px; height: 8px;
  background: var(--accent);
  border-radius: 50%;
  animation: pulse 2s infinite;
}
@keyframes pulse {
  0%, 100% { opacity: 1; transform: scale(1); }
  50% { opacity: 0.5; transform: scale(1.3); }
}
.hero h1 {
  font-size: clamp(2.2rem, 5vw, 3.8rem);
  font-weight: 900;
  line-height: 1.15;
  margin-bottom: 20px;
}
.hero h1 .brand {
  background: var(--gradient-gold);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}
.hero h1 .neon {
  color: var(--neon-blue);
  text-shadow: 0 0 20px rgba(0,212,255,0.5);
}
.hero-desc {
  font-size: 1.05rem;
  color: var(--text-muted);
  margin-bottom: 36px;
  max-width: 600px;
  line-height: 1.8;
}
.hero-actions { display: flex; gap: 16px; flex-wrap: wrap; }
.hero-stats {
  display: flex;
  gap: 40px;
  margin-top: 60px;
  flex-wrap: wrap;
}
.hero-stat { text-align: center; }
.hero-stat .num {
  font-size: 2rem;
  font-weight: 800;
  background: var(--gradient-gold);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}
.hero-stat .label { font-size: 0.8rem; color: var(--text-muted); }

/* ============================================
   视频卡片
   ============================================ */
.video-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 24px;
}
.video-card {
  background: var(--card-bg);
  border: 1px solid var(--card-border);
  border-radius: var(--radius-lg);
  overflow: hidden;
  transition: all var(--transition);
  cursor: pointer;
}
.video-card:hover {
  transform: translateY(-6px);
  border-color: var(--accent);
  box-shadow: var(--shadow-gold), 0 20px 40px rgba(0,0,0,0.4);
}
.video-thumb {
  position: relative;
  aspect-ratio: 16/9;
  overflow: hidden;
  background: #0d1b3e;
}
.video-thumb img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform 0.4s ease;
}
.video-card:hover .video-thumb img { transform: scale(1.05); }
.video-play-btn {
  position: absolute;
  inset: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  background: rgba(0,0,0,0.45);
  opacity: 0;
  transition: opacity var(--transition);
}
.video-card:hover .video-play-btn { opacity: 1; }
.play-icon {
  width: 60px;
  height: 60px;
  background: rgba(201,162,39,0.9);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  transform: scale(0.8);
  transition: transform var(--transition);
}
.video-card:hover .play-icon { transform: scale(1); }
.play-icon::after {
  content: '';
  border-style: solid;
  border-width: 10px 0 10px 18px;
  border-color: transparent transparent transparent #0a0e1a;
  margin-left: 4px;
}
.video-duration {
  position: absolute;
  bottom: 8px;
  right: 8px;
  background: rgba(0,0,0,0.8);
  color: #fff;
  font-size: 0.75rem;
  padding: 2px 7px;
  border-radius: 4px;
}
.video-info { padding: 16px; }
.video-meta {
  display: flex;
  align-items: center;
  gap: 8px;
  margin-bottom: 8px;
}
.video-title {
  font-size: 0.95rem;
  font-weight: 600;
  color: var(--text-main);
  margin-bottom: 10px;
  line-height: 1.4;
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
}
.video-stats {
  display: flex;
  gap: 14px;
  font-size: 0.78rem;
  color: var(--text-muted);
}
.video-stats span { display: flex; align-items: center; gap: 4px; }

/* ============================================
   Tab筛选
   ============================================ */
.tab-nav {
  display: flex;
  gap: 8px;
  flex-wrap: wrap;
  margin-bottom: 32px;
  justify-content: center;
}
.tab-btn {
  padding: 8px 20px;
  border-radius: 20px;
  border: 1.5px solid rgba(201,162,39,0.25);
  background: transparent;
  color: var(--text-muted);
  font-size: 0.88rem;
  cursor: pointer;
  transition: all var(--transition);
  font-family: var(--font-main);
}
.tab-btn:hover, .tab-btn.active {
  background: var(--accent);
  color: #0a0e1a;
  border-color: var(--accent);
  font-weight: 700;
}

/* ============================================
   专家展示
   ============================================ */
.experts-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(240px, 1fr));
  gap: 24px;
}
.expert-card {
  background: var(--card-bg);
  border: 1px solid var(--card-border);
  border-radius: var(--radius-lg);
  padding: 28px 20px;
  text-align: center;
  transition: all var(--transition);
}
.expert-card:hover {
  border-color: var(--accent);
  box-shadow: var(--shadow-gold);
  transform: translateY(-4px);
}
.expert-avatar {
  width: 88px;
  height: 88px;
  border-radius: 50%;
  object-fit: cover;
  margin: 0 auto 16px;
  border: 3px solid var(--accent);
  box-shadow: 0 0 15px rgba(201,162,39,0.3);
}
.expert-name {
  font-size: 1.05rem;
  font-weight: 700;
  color: var(--text-main);
  margin-bottom: 4px;
}
.expert-title {
  font-size: 0.82rem;
  color: var(--accent);
  margin-bottom: 12px;
}
.expert-desc {
  font-size: 0.83rem;
  color: var(--text-muted);
  line-height: 1.6;
  margin-bottom: 16px;
}
.expert-links { display: flex; gap: 8px; justify-content: center; flex-wrap: wrap; }

/* ============================================
   社区功能
   ============================================ */
.community-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
  gap: 20px;
}
.community-card {
  background: var(--card-bg);
  border: 1px solid var(--card-border);
  border-radius: var(--radius-lg);
  padding: 28px 20px;
  text-align: center;
  transition: all var(--transition);
}
.community-card:hover {
  border-color: var(--neon-blue);
  box-shadow: var(--shadow-neon);
  transform: translateY(-4px);
}
.community-icon {
  font-size: 2.5rem;
  margin-bottom: 14px;
  display: block;
}
.community-name {
  font-size: 1rem;
  font-weight: 700;
  color: var(--text-main);
  margin-bottom: 8px;
}
.community-desc {
  font-size: 0.82rem;
  color: var(--text-muted);
  line-height: 1.6;
}
.community-count {
  margin-top: 12px;
  font-size: 0.78rem;
  color: var(--neon-blue);
}

/* ============================================
   AI赋能模块
   ============================================ */
.ai-features {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
  gap: 24px;
}
.ai-card {
  background: linear-gradient(135deg, rgba(13,27,62,0.8), rgba(26,10,46,0.8));
  border: 1px solid rgba(0,212,255,0.2);
  border-radius: var(--radius-lg);
  padding: 32px 24px;
  transition: all var(--transition);
  position: relative;
  overflow: hidden;
}
.ai-card::before {
  content: '';
  position: absolute;
  top: 0; left: 0; right: 0;
  height: 2px;
  background: var(--gradient-neon);
}
.ai-card:hover {
  border-color: var(--neon-blue);
  box-shadow: var(--shadow-neon);
  transform: translateY(-4px);
}
.ai-icon {
  font-size: 2.2rem;
  margin-bottom: 16px;
}
.ai-title {
  font-size: 1.1rem;
  font-weight: 700;
  color: var(--neon-blue);
  margin-bottom: 10px;
}
.ai-desc {
  font-size: 0.88rem;
  color: var(--text-muted);
  line-height: 1.7;
}

/* ============================================
   合作品牌Logo墙
   ============================================ */
.partners-grid {
  display: flex;
  flex-wrap: wrap;
  gap: 16px;
  justify-content: center;
  align-items: center;
}
.partner-item {
  background: var(--card-bg);
  border: 1px solid var(--card-border);
  border-radius: var(--radius);
  padding: 16px 28px;
  font-size: 0.9rem;
  font-weight: 600;
  color: var(--text-muted);
  transition: all var(--transition);
  white-space: nowrap;
}
.partner-item:hover {
  color: var(--accent);
  border-color: var(--accent);
  background: rgba(201,162,39,0.08);
}

/* ============================================
   用户评论
   ============================================ */
.reviews-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 20px;
}
.review-card {
  background: var(--card-bg);
  border: 1px solid var(--card-border);
  border-radius: var(--radius-lg);
  padding: 24px;
  transition: all var(--transition);
}
.review-card:hover {
  border-color: var(--accent);
  box-shadow: var(--shadow-gold);
}
.review-stars {
  color: var(--accent);
  font-size: 0.9rem;
  margin-bottom: 12px;
  letter-spacing: 2px;
}
.review-text {
  font-size: 0.88rem;
  color: var(--text-muted);
  line-height: 1.7;
  margin-bottom: 16px;
  font-style: italic;
}
.review-user {
  display: flex;
  align-items: center;
  gap: 10px;
}
.review-avatar {
  width: 36px;
  height: 36px;
  border-radius: 50%;
  background: var(--gradient-gold);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 0.85rem;
  font-weight: 700;
  color: #0a0e1a;
  flex-shrink: 0;
}
.review-name { font-size: 0.88rem; font-weight: 600; color: var(--text-main); }
.review-date { font-size: 0.75rem; color: var(--text-muted); }

/* ============================================
   FAQ
   ============================================ */
.faq-list { max-width: 800px; margin: 0 auto; }
.faq-item {
  background: var(--card-bg);
  border: 1px solid var(--card-border);
  border-radius: var(--radius);
  margin-bottom: 12px;
  overflow: hidden;
  transition: border-color var(--transition);
}
.faq-item.open { border-color: var(--accent); }
.faq-question {
  padding: 18px 24px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  cursor: pointer;
  font-size: 0.95rem;
  font-weight: 600;
  color: var(--text-main);
  transition: color var(--transition);
  user-select: none;
}
.faq-question:hover { color: var(--accent); }
.faq-arrow {
  width: 20px;
  height: 20px;
  border-radius: 50%;
  background: rgba(201,162,39,0.15);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 0.75rem;
  color: var(--accent);
  transition: transform var(--transition);
  flex-shrink: 0;
}
.faq-item.open .faq-arrow { transform: rotate(180deg); }
.faq-answer {
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.35s ease, padding 0.35s ease;
}
.faq-answer-inner {
  padding: 0 24px 18px;
  font-size: 0.88rem;
  color: var(--text-muted);
  line-height: 1.8;
}
.faq-item.open .faq-answer { max-height: 300px; }

/* ============================================
   联系我们
   ============================================ */
.contact-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 40px;
  align-items: start;
}
.contact-info { }
.contact-item {
  display: flex;
  gap: 16px;
  margin-bottom: 24px;
  align-items: flex-start;
}
.contact-icon {
  width: 44px;
  height: 44px;
  background: rgba(201,162,39,0.1);
  border: 1px solid rgba(201,162,39,0.3);
  border-radius: var(--radius);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.2rem;
  flex-shrink: 0;
}
.contact-label { font-size: 0.8rem; color: var(--text-muted); margin-bottom: 4px; }
.contact-value { font-size: 0.95rem; color: var(--text-main); font-weight: 500; }
.qrcode-row {
  display: flex;
  gap: 24px;
  flex-wrap: wrap;
}
.qrcode-item { text-align: center; }
.qrcode-item img {
  width: 120px;
  height: 120px;
  border-radius: var(--radius);
  border: 2px solid var(--card-border);
  object-fit: cover;
}
.qrcode-label {
  font-size: 0.78rem;
  color: var(--text-muted);
  margin-top: 8px;
}

/* ============================================
   社交分享
   ============================================ */
.share-bar {
  display: flex;
  gap: 12px;
  flex-wrap: wrap;
  justify-content: center;
  margin-top: 20px;
}
.share-btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 10px 20px;
  border-radius: 24px;
  font-size: 0.85rem;
  font-weight: 600;
  cursor: pointer;
  border: none;
  transition: all var(--transition);
  font-family: var(--font-main);
}
.share-wechat { background: #07c160; color: #fff; }
.share-weibo { background: #e6162d; color: #fff; }
.share-douyin { background: #010101; color: #fff; border: 1px solid #333; }
.share-bilibili { background: #00a1d6; color: #fff; }
.share-btn:hover { transform: translateY(-2px); box-shadow: 0 6px 20px rgba(0,0,0,0.3); }

/* ============================================
   视频弹窗
   ============================================ */
.video-modal {
  display: none;
  position: fixed;
  inset: 0;
  z-index: 9999;
  background: rgba(0,0,0,0.85);
  align-items: center;
  justify-content: center;
}
.video-modal.active { display: flex; }
.modal-inner {
  background: var(--card-bg);
  border: 1px solid var(--card-border);
  border-radius: var(--radius-lg);
  width: 90%;
  max-width: 800px;
  overflow: hidden;
  position: relative;
}
.modal-close {
  position: absolute;
  top: 12px; right: 16px;
  background: rgba(255,255,255,0.1);
  border: none;
  color: #fff;
  font-size: 1.2rem;
  width: 32px; height: 32px;
  border-radius: 50%;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 10;
  transition: background var(--transition);
}
.modal-close:hover { background: var(--accent2); }
.modal-video-wrap {
  aspect-ratio: 16/9;
  background: #000;
  display: flex;
  align-items: center;
  justify-content: center;
}
.modal-video-placeholder {
  text-align: center;
  color: var(--text-muted);
}
.modal-video-placeholder .big-play {
  font-size: 4rem;
  margin-bottom: 12px;
  color: var(--accent);
}
.modal-info { padding: 20px 24px; }
.modal-title { font-size: 1.05rem; font-weight: 700; margin-bottom: 8px; }
.modal-desc { font-size: 0.85rem; color: var(--text-muted); }

/* ============================================
   面包屑
   ============================================ */
.breadcrumb {
  padding: 12px 0;
  font-size: 0.82rem;
  color: var(--text-muted);
  display: flex;
  align-items: center;
  gap: 6px;
  flex-wrap: wrap;
}
.breadcrumb a { color: var(--text-muted); }
.breadcrumb a:hover { color: var(--accent); }
.breadcrumb .sep { color: rgba(255,255,255,0.2); }
.breadcrumb .current { color: var(--accent); }

/* ============================================
   页脚
   ============================================ */
#footer {
  background: #060a14;
  border-top: 1px solid rgba(201,162,39,0.15);
  padding: 60px 0 30px;
}
.footer-grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1fr;
  gap: 40px;
  margin-bottom: 40px;
}
.footer-brand-logo {
  height: 48px;
  width: auto;
  margin-bottom: 16px;
}
.footer-desc {
  font-size: 0.85rem;
  color: var(--text-muted);
  line-height: 1.8;
  margin-bottom: 20px;
}
.footer-col h4 {
  font-size: 0.95rem;
  font-weight: 700;
  color: var(--accent);
  margin-bottom: 16px;
  padding-bottom: 8px;
  border-bottom: 1px solid rgba(201,162,39,0.2);
}
.footer-col ul li { margin-bottom: 10px; }
.footer-col ul li a {
  font-size: 0.85rem;
  color: var(--text-muted);
  transition: color var(--transition);
}
.footer-col ul li a:hover { color: var(--accent); }
.footer-bottom {
  border-top: 1px solid rgba(255,255,255,0.06);
  padding-top: 24px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 12px;
}
.footer-copy {
  font-size: 0.82rem;
  color: var(--text-muted);
}
.footer-copy a { color: var(--text-muted); }
.footer-copy a:hover { color: var(--accent); }
.footer-update {
  font-size: 0.8rem;
  color: var(--text-muted);
}
.footer-update span { color: var(--accent); }

/* ============================================
   回到顶部
   ============================================ */
#back-top {
  position: fixed;
  bottom: 30px; right: 30px;
  width: 44px; height: 44px;
  background: var(--accent);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  opacity: 0;
  transform: translateY(20px);
  transition: all var(--transition);
  z-index: 999;
  border: none;
  color: #0a0e1a;
  font-size: 1.1rem;
  box-shadow: var(--shadow-gold);
}
#back-top.visible { opacity: 1; transform: translateY(0); }
#back-top:hover { background: var(--neon-gold); }

/* ============================================
   内页Banner
   ============================================ */
.page-hero {
  padding: 140px 0 60px;
  background: var(--gradient-hero);
  border-bottom: 1px solid rgba(201,162,39,0.15);
  position: relative;
  overflow: hidden;
}
.page-hero::after {
  content: '';
  position: absolute;
  bottom: 0; left: 0; right: 0;
  height: 1px;
  background: var(--gradient-gold);
}
.page-hero h1 {
  font-size: 2.2rem;
  font-weight: 800;
  background: var(--gradient-gold);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  margin-bottom: 12px;
}
.page-hero p {
  color: var(--text-muted);
  font-size: 0.95rem;
}

/* ============================================
   通用卡片
   ============================================ */
.card {
  background: var(--card-bg);
  border: 1px solid var(--card-border);
  border-radius: var(--radius-lg);
  padding: 28px;
  transition: all var(--transition);
}
.card:hover {
  border-color: var(--accent);
  box-shadow: var(--shadow-gold);
}

/* ============================================
   响应式
   ============================================ */
@media (max-width: 1024px) {
  .footer-grid { grid-template-columns: 1fr 1fr; }
  .contact-grid { grid-template-columns: 1fr; }
}
@media (max-width: 768px) {
  .nav-menu { display: none; flex-direction: column; position: absolute; top: 64px; left: 0; right: 0; background: rgba(10,14,26,0.98); padding: 16px; border-bottom: 1px solid rgba(201,162,39,0.2); }
  .nav-menu.open { display: flex; }
  .nav-toggle { display: flex; }
  .nav-search { display: none; }
  .hero { min-height: auto; padding: 120px 0 60px; }
  .hero h1 { font-size: 1.8rem; }
  .hero-stats { gap: 24px; }
  .video-grid { grid-template-columns: 1fr 1fr; }
  .ai-features { grid-template-columns: 1fr; }
  .footer-grid { grid-template-columns: 1fr; gap: 24px; }
  .footer-bottom { flex-direction: column; text-align: center; }
  .section { padding: 50px 0; }
  .section-title { font-size: 1.6rem; }
}
@media (max-width: 480px) {
  .video-grid { grid-template-columns: 1fr; }
  .experts-grid { grid-template-columns: 1fr 1fr; }
  .community-grid { grid-template-columns: 1fr 1fr; }
  .hero-actions { flex-direction: column; }
  .hero-actions .btn { width: 100%; justify-content: center; }
}

/* ============================================
   动画
   ============================================ */
@keyframes fadeInUp {
  from { opacity: 0; transform: translateY(30px); }
  to { opacity: 1; transform: translateY(0); }
}
.fade-in { animation: fadeInUp 0.6s ease forwards; }
.fade-in-delay-1 { animation-delay: 0.1s; opacity: 0; }
.fade-in-delay-2 { animation-delay: 0.2s; opacity: 0; }
.fade-in-delay-3 { animation-delay: 0.3s; opacity: 0; }

/* ============================================
   工具类
   ============================================ */
.text-gold { color: var(--accent); }
.text-neon { color: var(--neon-blue); }
.text-muted { color: var(--text-muted); }
.text-center { text-align: center; }
.mt-8 { margin-top: 8px; }
.mt-16 { margin-top: 16px; }
.mt-24 { margin-top: 24px; }
.mt-40 { margin-top: 40px; }
.mb-24 { margin-bottom: 24px; }
.mb-40 { margin-bottom: 40px; }
.flex { display: flex; }
.flex-center { display: flex; align-items: center; justify-content: center; }
.gap-8 { gap: 8px; }
.gap-16 { gap: 16px; }
.hidden { display: none !important; }