/* =============================================
   淘AV - 影视传媒社区 主样式文件
   Brand: 淘AV | Domain: 311313.cn
   ============================================= */

/* ---- CSS变量 / 原创配色方案 ---- */
:root {
  --primary:      #8B1A1A;   /* 深酒红 */
  --primary-dark: #5C0F0F;
  --primary-light:#C0392B;
  --gold:         #D4AF37;
  --gold-light:   #F0D060;
  --dark:         #0D0D0D;
  --dark2:        #1A1A1A;
  --dark3:        #252525;
  --mid:          #3A3A3A;
  --light:        #F5F0E8;
  --white:        #FFFFFF;
  --text:         #E8E0D0;
  --text-muted:   #A09080;
  --border:       rgba(212,175,55,0.25);
  --shadow:       0 4px 24px rgba(0,0,0,0.45);
  --radius:       10px;
  --radius-lg:    18px;
  --transition:   0.3s ease;
  --font-main:    'PingFang SC','Microsoft YaHei','Hiragino Sans GB',sans-serif;
}

/* ---- Reset & Base ---- */
*, *::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(--dark);
  color: var(--text);
  line-height: 1.7;
  overflow-x: hidden;
}
a { color: var(--gold); text-decoration: none; transition: color var(--transition); }
a:hover { color: var(--gold-light); }
img { max-width: 100%; height: auto; display: block; }
ul, ol { list-style: none; }
button { cursor: pointer; font-family: var(--font-main); }

/* ---- 通用容器 ---- */
.container { max-width: 1200px; margin: 0 auto; padding: 0 20px; }
.section { padding: 70px 0; }
.section-alt { background: var(--dark2); }
.section-title {
  font-size: 2rem;
  font-weight: 700;
  text-align: center;
  margin-bottom: 12px;
  color: var(--white);
  position: relative;
}
.section-title span { color: var(--gold); }
.section-subtitle {
  text-align: center;
  color: var(--text-muted);
  margin-bottom: 48px;
  font-size: 1rem;
}
.section-title::after {
  content: '';
  display: block;
  width: 60px;
  height: 3px;
  background: linear-gradient(90deg, var(--primary), var(--gold));
  margin: 14px auto 0;
  border-radius: 2px;
}

/* ---- 按钮 ---- */
.btn {
  display: inline-block;
  padding: 11px 28px;
  border-radius: 6px;
  font-size: 0.95rem;
  font-weight: 600;
  transition: all var(--transition);
  border: none;
  outline: none;
}
.btn-primary {
  background: linear-gradient(135deg, var(--primary), var(--primary-light));
  color: var(--white);
  box-shadow: 0 4px 15px rgba(139,26,26,0.4);
}
.btn-primary:hover {
  background: linear-gradient(135deg, var(--primary-light), var(--primary));
  color: var(--white);
  transform: translateY(-2px);
  box-shadow: 0 6px 20px rgba(139,26,26,0.55);
}
.btn-gold {
  background: linear-gradient(135deg, var(--gold), var(--gold-light));
  color: var(--dark);
  box-shadow: 0 4px 15px rgba(212,175,55,0.35);
}
.btn-gold:hover {
  transform: translateY(-2px);
  box-shadow: 0 6px 20px rgba(212,175,55,0.5);
  color: var(--dark);
}
.btn-outline {
  background: transparent;
  border: 1.5px solid var(--gold);
  color: var(--gold);
}
.btn-outline:hover {
  background: var(--gold);
  color: var(--dark);
}

/* ---- 顶部公告栏 ---- */
.top-bar {
  background: linear-gradient(90deg, var(--primary-dark), var(--primary));
  padding: 7px 0;
  font-size: 0.82rem;
  color: rgba(255,255,255,0.85);
}
.top-bar .container {
  display: flex;
  justify-content: space-between;
  align-items: center;
}
.top-bar-links a {
  color: rgba(255,255,255,0.85);
  margin-left: 16px;
  font-size: 0.82rem;
}
.top-bar-links a:hover { color: var(--gold-light); }

/* ---- 导航栏 ---- */
.navbar {
  position: sticky;
  top: 0;
  z-index: 1000;
  background: rgba(13,13,13,0.97);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--border);
  padding: 0;
}
.navbar-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 68px;
}
.navbar-brand {
  display: flex;
  align-items: center;
  gap: 12px;
  text-decoration: none;
}
.navbar-brand img.site-favicon {
  width: 36px;
  height: 36px;
  border-radius: 50%;
  object-fit: cover;
  border: 2px solid var(--gold);
}
.navbar-brand img.site-logo {
  height: 44px;
  width: auto;
}
.brand-text {
  display: flex;
  flex-direction: column;
  line-height: 1.2;
}
.brand-name {
  font-size: 1.3rem;
  font-weight: 800;
  color: var(--white);
  letter-spacing: 1px;
}
.brand-name em { color: var(--gold); font-style: normal; }
.brand-slogan {
  font-size: 0.72rem;
  color: var(--text-muted);
  letter-spacing: 0.5px;
}
.nav-menu {
  display: flex;
  align-items: center;
  gap: 4px;
}
.nav-menu > li { position: relative; }
.nav-menu > li > a {
  display: block;
  padding: 8px 14px;
  color: var(--text);
  font-size: 0.92rem;
  font-weight: 500;
  border-radius: 6px;
  transition: all var(--transition);
  white-space: nowrap;
}
.nav-menu > li > a:hover,
.nav-menu > li > a.active {
  color: var(--gold);
  background: rgba(212,175,55,0.08);
}
.nav-menu > li:hover .dropdown { display: block; }
.dropdown {
  display: none;
  position: absolute;
  top: 100%;
  left: 0;
  min-width: 160px;
  background: var(--dark2);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  padding: 8px 0;
  z-index: 100;
}
.dropdown a {
  display: block;
  padding: 9px 18px;
  color: var(--text);
  font-size: 0.88rem;
  transition: all var(--transition);
}
.dropdown a:hover { background: rgba(212,175,55,0.1); color: var(--gold); }

/* ---- 搜索框 ---- */
.search-bar-wrap {
  background: var(--dark3);
  border-bottom: 1px solid var(--border);
  padding: 10px 0;
}
.search-bar-inner {
  display: flex;
  align-items: center;
  gap: 10px;
  max-width: 600px;
  margin: 0 auto;
}
.search-input {
  flex: 1;
  background: var(--dark2);
  border: 1.5px solid var(--border);
  border-radius: 24px;
  padding: 9px 20px;
  color: var(--text);
  font-size: 0.92rem;
  outline: none;
  transition: border-color var(--transition);
}
.search-input:focus { border-color: var(--gold); }
.search-input::placeholder { color: var(--text-muted); }
.search-btn {
  background: linear-gradient(135deg, var(--primary), var(--primary-light));
  color: var(--white);
  border: none;
  border-radius: 24px;
  padding: 9px 22px;
  font-size: 0.92rem;
  font-weight: 600;
  transition: all var(--transition);
}
.search-btn:hover { opacity: 0.9; transform: scale(1.03); }
.search-hot {
  text-align: center;
  font-size: 0.78rem;
  color: var(--text-muted);
  margin-top: 6px;
}
.search-hot a {
  color: var(--text-muted);
  margin: 0 5px;
  font-size: 0.78rem;
}
.search-hot a:hover { color: var(--gold); }

/* ---- 面包屑 ---- */
.breadcrumb {
  padding: 12px 0;
  font-size: 0.83rem;
  color: var(--text-muted);
}
.breadcrumb a { color: var(--text-muted); }
.breadcrumb a:hover { color: var(--gold); }
.breadcrumb span { margin: 0 6px; }

/* ---- Hero Banner ---- */
.hero {
  position: relative;
  min-height: 520px;
  display: flex;
  align-items: center;
  overflow: hidden;
  background: var(--dark);
}
.hero-bg {
  position: absolute;
  inset: 0;
  background-image: url('../images/banner_hero.jpg');
  background-size: cover;
  background-position: center;
  filter: brightness(0.45);
  z-index: 0;
}
.hero-overlay {
  position: absolute;
  inset: 0;
  background: linear-gradient(135deg, rgba(139,26,26,0.55) 0%, rgba(13,13,13,0.7) 60%);
  z-index: 1;
}
.hero-content {
  position: relative;
  z-index: 2;
  max-width: 650px;
}
.hero-tag {
  display: inline-block;
  background: var(--primary);
  color: var(--white);
  font-size: 0.78rem;
  padding: 4px 14px;
  border-radius: 20px;
  margin-bottom: 16px;
  letter-spacing: 1px;
}
.hero h1 {
  font-size: 2.8rem;
  font-weight: 900;
  line-height: 1.2;
  color: var(--white);
  margin-bottom: 18px;
}
.hero h1 em { color: var(--gold); font-style: normal; }
.hero p {
  font-size: 1.05rem;
  color: rgba(255,255,255,0.8);
  margin-bottom: 28px;
  line-height: 1.8;
}
.hero-btns { display: flex; gap: 14px; flex-wrap: wrap; }
.hero-stats {
  display: flex;
  gap: 36px;
  margin-top: 36px;
  flex-wrap: wrap;
}
.hero-stat-item { text-align: center; }
.hero-stat-num {
  font-size: 1.8rem;
  font-weight: 800;
  color: var(--gold);
  display: block;
}
.hero-stat-label {
  font-size: 0.78rem;
  color: rgba(255,255,255,0.65);
}

/* ---- 视频卡片 ---- */
.video-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 22px;
}
.video-card {
  background: var(--dark2);
  border-radius: var(--radius-lg);
  overflow: hidden;
  border: 1px solid var(--border);
  transition: all var(--transition);
  cursor: pointer;
}
.video-card:hover {
  transform: translateY(-5px);
  box-shadow: 0 12px 36px rgba(139,26,26,0.35);
  border-color: rgba(212,175,55,0.5);
}
.video-thumb {
  position: relative;
  overflow: hidden;
  aspect-ratio: 16/9;
  background: var(--dark3);
}
.video-thumb img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform 0.4s ease;
}
.video-card:hover .video-thumb img { transform: scale(1.06); }
.video-play-btn {
  position: absolute;
  inset: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  background: rgba(0,0,0,0);
  opacity: 0;
  transition: all var(--transition);
}
.video-card:hover .video-play-btn {
  opacity: 1;
  background: rgba(0,0,0,0.45);
}
.video-play-icon {
  width: 58px;
  height: 58px;
  background: rgba(212,175,55,0.92);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  transform: scale(0.8);
  transition: transform var(--transition);
}
.video-card:hover .video-play-icon { transform: scale(1); }
.video-play-icon::after {
  content: '';
  width: 0;
  height: 0;
  border-style: solid;
  border-width: 11px 0 11px 20px;
  border-color: transparent transparent transparent var(--dark);
  margin-left: 4px;
}
.video-duration {
  position: absolute;
  bottom: 8px;
  right: 10px;
  background: rgba(0,0,0,0.75);
  color: var(--white);
  font-size: 0.75rem;
  padding: 2px 7px;
  border-radius: 4px;
}
.video-badge {
  position: absolute;
  top: 10px;
  left: 10px;
  background: var(--primary);
  color: var(--white);
  font-size: 0.72rem;
  padding: 3px 9px;
  border-radius: 4px;
  font-weight: 600;
}
.video-info { padding: 14px 16px; }
.video-title {
  font-size: 0.95rem;
  font-weight: 600;
  color: var(--white);
  margin-bottom: 8px;
  line-height: 1.4;
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
}
.video-meta {
  display: flex;
  align-items: center;
  gap: 12px;
  font-size: 0.78rem;
  color: var(--text-muted);
}
.video-meta span { display: flex; align-items: center; gap: 4px; }
.video-stats {
  display: flex;
  gap: 14px;
  margin-top: 8px;
  font-size: 0.78rem;
  color: var(--text-muted);
}

/* ---- 专家卡片 ---- */
.expert-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(260px, 1fr));
  gap: 24px;
}
.expert-card {
  background: var(--dark2);
  border-radius: var(--radius-lg);
  overflow: hidden;
  border: 1px solid var(--border);
  text-align: center;
  transition: all var(--transition);
}
.expert-card:hover {
  transform: translateY(-4px);
  box-shadow: 0 10px 30px rgba(0,0,0,0.4);
  border-color: rgba(212,175,55,0.4);
}
.expert-photo {
  width: 100%;
  aspect-ratio: 3/4;
  object-fit: cover;
  object-position: top;
}
.expert-info { padding: 18px; }
.expert-name {
  font-size: 1.1rem;
  font-weight: 700;
  color: var(--white);
  margin-bottom: 4px;
}
.expert-title {
  font-size: 0.82rem;
  color: var(--gold);
  margin-bottom: 10px;
}
.expert-desc {
  font-size: 0.83rem;
  color: var(--text-muted);
  line-height: 1.6;
  margin-bottom: 14px;
}
.expert-tags { display: flex; flex-wrap: wrap; gap: 6px; justify-content: center; margin-bottom: 14px; }
.tag {
  background: rgba(139,26,26,0.25);
  border: 1px solid rgba(139,26,26,0.4);
  color: var(--text);
  font-size: 0.72rem;
  padding: 3px 10px;
  border-radius: 20px;
}
.expert-btns { display: flex; gap: 8px; justify-content: center; }

/* ---- 社区功能 ---- */
.community-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(220px, 1fr));
  gap: 20px;
}
.community-card {
  background: var(--dark2);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 28px 20px;
  text-align: center;
  transition: all var(--transition);
}
.community-card:hover {
  border-color: var(--gold);
  background: var(--dark3);
  transform: translateY(-3px);
}
.community-icon {
  font-size: 2.4rem;
  margin-bottom: 14px;
  display: block;
}
.community-card h3 {
  font-size: 1rem;
  color: var(--white);
  margin-bottom: 8px;
}
.community-card p {
  font-size: 0.82rem;
  color: var(--text-muted);
  line-height: 1.6;
}

/* ---- AI赋能 ---- */
.ai-section {
  position: relative;
  overflow: hidden;
}
.ai-bg {
  position: absolute;
  inset: 0;
  background-image: url('../images/ai_section_bg.jpg');
  background-size: cover;
  background-position: center;
  filter: brightness(0.2);
  z-index: 0;
}
.ai-section .container { position: relative; z-index: 1; }
.ai-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 22px;
}
.ai-card {
  background: rgba(26,26,26,0.85);
  border: 1px solid rgba(212,175,55,0.2);
  border-radius: var(--radius-lg);
  padding: 28px 22px;
  backdrop-filter: blur(6px);
  transition: all var(--transition);
}
.ai-card:hover {
  border-color: var(--gold);
  background: rgba(26,26,26,0.95);
}
.ai-card-icon {
  width: 52px;
  height: 52px;
  background: linear-gradient(135deg, var(--primary), var(--primary-light));
  border-radius: 14px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.5rem;
  margin-bottom: 16px;
}
.ai-card h3 { font-size: 1.05rem; color: var(--white); margin-bottom: 8px; }
.ai-card p { font-size: 0.85rem; color: var(--text-muted); line-height: 1.7; }

/* ---- 合作品牌 ---- */
.partners-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(160px, 1fr));
  gap: 16px;
}
.partner-item {
  background: var(--dark2);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 18px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 0.9rem;
  color: var(--text-muted);
  font-weight: 600;
  text-align: center;
  min-height: 70px;
  transition: all var(--transition);
}
.partner-item:hover {
  border-color: var(--gold);
  color: var(--gold);
  background: var(--dark3);
}

/* ---- 用户评价 ---- */
.reviews-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
  gap: 22px;
}
.review-card {
  background: var(--dark2);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 24px;
  position: relative;
  transition: all var(--transition);
}
.review-card:hover { border-color: rgba(212,175,55,0.4); }
.review-card::before {
  content: '"';
  position: absolute;
  top: 14px;
  right: 20px;
  font-size: 4rem;
  color: rgba(212,175,55,0.15);
  font-family: Georgia, serif;
  line-height: 1;
}
.review-stars { color: var(--gold); font-size: 0.9rem; margin-bottom: 10px; }
.review-text {
  font-size: 0.88rem;
  color: var(--text);
  line-height: 1.7;
  margin-bottom: 16px;
}
.review-author {
  display: flex;
  align-items: center;
  gap: 10px;
}
.review-avatar {
  width: 40px;
  height: 40px;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--primary), var(--gold));
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1rem;
  color: var(--white);
  font-weight: 700;
  flex-shrink: 0;
}
.review-name { font-size: 0.88rem; font-weight: 600; color: var(--white); }
.review-date { font-size: 0.75rem; color: var(--text-muted); }

/* ---- FAQ ---- */
.faq-list { max-width: 800px; margin: 0 auto; }
.faq-item {
  background: var(--dark2);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  margin-bottom: 12px;
  overflow: hidden;
}
.faq-question {
  padding: 18px 22px;
  font-size: 0.95rem;
  font-weight: 600;
  color: var(--white);
  cursor: pointer;
  display: flex;
  justify-content: space-between;
  align-items: center;
  transition: background var(--transition);
}
.faq-question:hover { background: var(--dark3); }
.faq-question .faq-icon {
  color: var(--gold);
  font-size: 1.2rem;
  transition: transform var(--transition);
  flex-shrink: 0;
}
.faq-item.open .faq-icon { transform: rotate(45deg); }
.faq-answer {
  display: none;
  padding: 0 22px 18px;
  font-size: 0.88rem;
  color: var(--text-muted);
  line-height: 1.8;
  border-top: 1px solid var(--border);
  padding-top: 14px;
}
.faq-item.open .faq-answer { display: block; }

/* ---- 联系 ---- */
.contact-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 32px;
}
.contact-info-box {
  background: var(--dark2);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 32px;
}
.contact-info-box h3 {
  font-size: 1.2rem;
  color: var(--gold);
  margin-bottom: 20px;
}
.contact-item {
  display: flex;
  gap: 14px;
  margin-bottom: 16px;
  align-items: flex-start;
}
.contact-icon {
  width: 40px;
  height: 40px;
  background: rgba(139,26,26,0.2);
  border-radius: 10px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.1rem;
  flex-shrink: 0;
}
.contact-label { font-size: 0.78rem; color: var(--text-muted); }
.contact-value { font-size: 0.92rem; color: var(--text); font-weight: 500; }
.qr-grid { display: flex; gap: 20px; flex-wrap: wrap; }
.qr-item { text-align: center; }
.qr-item img { width: 110px; height: 110px; border-radius: 8px; border: 2px solid var(--border); }
.qr-item p { font-size: 0.78rem; color: var(--text-muted); margin-top: 6px; }

/* ---- 社交分享 ---- */
.share-bar {
  display: flex;
  align-items: center;
  gap: 12px;
  flex-wrap: wrap;
}
.share-label { font-size: 0.85rem; color: var(--text-muted); }
.share-btn {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 7px 16px;
  border-radius: 20px;
  font-size: 0.82rem;
  font-weight: 600;
  border: none;
  cursor: pointer;
  transition: all var(--transition);
}
.share-wechat { background: #07C160; color: #fff; }
.share-weibo  { background: #E6162D; color: #fff; }
.share-douyin { background: #000; color: #fff; border: 1px solid #333; }
.share-bilibili { background: #00A1D6; color: #fff; }
.share-btn:hover { opacity: 0.85; transform: scale(1.04); }

/* ---- 页脚 ---- */
.footer {
  background: var(--dark2);
  border-top: 1px solid var(--border);
  padding: 50px 0 0;
}
.footer-grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1fr;
  gap: 36px;
  padding-bottom: 36px;
}
.footer-brand img { height: 48px; margin-bottom: 14px; }
.footer-brand p { font-size: 0.85rem; color: var(--text-muted); line-height: 1.7; margin-bottom: 16px; }
.footer-col h4 {
  font-size: 0.95rem;
  color: var(--gold);
  margin-bottom: 16px;
  font-weight: 700;
}
.footer-col ul li { margin-bottom: 9px; }
.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(--gold); }
.footer-bottom {
  border-top: 1px solid var(--border);
  padding: 18px 0;
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 10px;
}
.footer-bottom p { font-size: 0.8rem; color: var(--text-muted); }
.footer-bottom a { color: var(--text-muted); }
.footer-bottom a:hover { color: var(--gold); }
.footer-logo-bottom { height: 32px; }

/* ---- 汉堡菜单（移动端） ---- */
.nav-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  cursor: pointer;
  padding: 6px;
}
.nav-toggle span {
  display: block;
  width: 24px;
  height: 2px;
  background: var(--text);
  border-radius: 2px;
  transition: all var(--transition);
}

/* ---- 滚动进度条 ---- */
.scroll-progress {
  position: fixed;
  top: 0;
  left: 0;
  height: 3px;
  background: linear-gradient(90deg, var(--primary), var(--gold));
  z-index: 9999;
  width: 0%;
  transition: width 0.1s;
}

/* ---- 回顶部 ---- */
.back-to-top {
  position: fixed;
  bottom: 30px;
  right: 30px;
  width: 44px;
  height: 44px;
  background: linear-gradient(135deg, var(--primary), var(--primary-light));
  color: var(--white);
  border: none;
  border-radius: 50%;
  font-size: 1.2rem;
  display: none;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  box-shadow: 0 4px 15px rgba(139,26,26,0.4);
  z-index: 500;
  transition: all var(--transition);
}
.back-to-top:hover { transform: translateY(-3px); }
.back-to-top.show { display: flex; }

/* ---- 内页通用 ---- */
.page-header {
  background: linear-gradient(135deg, var(--dark2), var(--dark));
  border-bottom: 1px solid var(--border);
  padding: 40px 0 30px;
}
.page-header h1 {
  font-size: 2rem;
  font-weight: 800;
  color: var(--white);
  margin-bottom: 8px;
}
.page-header h1 span { color: var(--gold); }
.page-header p { color: var(--text-muted); font-size: 0.95rem; }

/* ---- 热门话题标签 ---- */
.hot-topics {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-bottom: 32px;
}
.hot-topic-tag {
  background: var(--dark3);
  border: 1px solid var(--border);
  color: var(--text-muted);
  padding: 6px 16px;
  border-radius: 20px;
  font-size: 0.82rem;
  cursor: pointer;
  transition: all var(--transition);
}
.hot-topic-tag:hover,
.hot-topic-tag.active {
  background: var(--primary);
  border-color: var(--primary);
  color: var(--white);
}

/* ---- 弹幕效果 ---- */
.danmu-wrap {
  background: var(--dark3);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  height: 44px;
  overflow: hidden;
  position: relative;
  margin-bottom: 24px;
}
.danmu-track {
  display: flex;
  gap: 60px;
  white-space: nowrap;
  animation: danmu-scroll 30s linear infinite;
  padding: 11px 0;
}
.danmu-item {
  font-size: 0.85rem;
  color: var(--text-muted);
  padding: 0 8px;
}
.danmu-item.hot { color: var(--gold); }
@keyframes danmu-scroll {
  0%   { transform: translateX(100%); }
  100% { transform: translateX(-100%); }
}

/* ---- 统计数字 ---- */
.stats-row {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 20px;
  margin: 40px 0;
}
.stat-box {
  background: var(--dark2);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 24px;
  text-align: center;
}
.stat-num {
  font-size: 2.2rem;
  font-weight: 900;
  color: var(--gold);
  display: block;
}
.stat-label { font-size: 0.82rem; color: var(--text-muted); margin-top: 4px; }

/* ---- 响应式 ---- */
@media (max-width: 1024px) {
  .footer-grid { grid-template-columns: 1fr 1fr; }
  .contact-grid { grid-template-columns: 1fr; }
  .stats-row { grid-template-columns: repeat(2, 1fr); }
}
@media (max-width: 768px) {
  .hero h1 { font-size: 1.9rem; }
  .section { padding: 48px 0; }
  .section-title { font-size: 1.6rem; }
  .nav-menu { display: none; flex-direction: column; position: absolute; top: 68px; left: 0; right: 0; background: var(--dark); border-bottom: 1px solid var(--border); padding: 12px 0; }
  .nav-menu.open { display: flex; }
  .nav-menu > li > a { padding: 12px 20px; border-radius: 0; }
  .dropdown { position: static; box-shadow: none; border: none; background: var(--dark3); }
  .nav-toggle { display: flex; }
  .navbar { position: relative; }
  .footer-grid { grid-template-columns: 1fr; }
  .video-grid { grid-template-columns: 1fr 1fr; }
  .stats-row { grid-template-columns: repeat(2, 1fr); }
  .hero-stats { gap: 20px; }
  .top-bar .container { flex-direction: column; gap: 4px; text-align: center; }
}
@media (max-width: 480px) {
  .video-grid { grid-template-columns: 1fr; }
  .hero h1 { font-size: 1.5rem; }
  .hero-btns { flex-direction: column; }
  .expert-grid { grid-template-columns: 1fr; }
  .community-grid { grid-template-columns: 1fr 1fr; }
  .stats-row { grid-template-columns: 1fr 1fr; }
}

/* ---- 懒加载占位 ---- */
img[data-src] { background: var(--dark3); min-height: 80px; }

/* ---- 动画 ---- */
@keyframes fadeInUp {
  from { opacity: 0; transform: translateY(24px); }
  to   { opacity: 1; transform: translateY(0); }
}
.fade-in-up { animation: fadeInUp 0.6s ease both; }
.delay-1 { animation-delay: 0.1s; }
.delay-2 { animation-delay: 0.2s; }
.delay-3 { animation-delay: 0.3s; }