/* ========================================
   探花 - 影视传媒 & 视频社区
   主样式文件 style.css
   域名: 789.cn
   ======================================== */

/* CSS变量 - 原创配色方案 */
:root {
  --primary: #E8453C;
  --primary-dark: #C0392B;
  --primary-light: #FF6B6B;
  --secondary: #F5A623;
  --secondary-dark: #D4891A;
  --accent: #7B2FBE;
  --accent-light: #9B59B6;
  --dark: #1A1A2E;
  --dark-2: #16213E;
  --dark-3: #0F3460;
  --text-primary: #2C2C2C;
  --text-secondary: #5A5A5A;
  --text-light: #888888;
  --bg-light: #F8F6F3;
  --bg-white: #FFFFFF;
  --border: #E8E0D8;
  --shadow-sm: 0 2px 8px rgba(0,0,0,0.08);
  --shadow-md: 0 4px 20px rgba(0,0,0,0.12);
  --shadow-lg: 0 8px 40px rgba(0,0,0,0.16);
  --radius-sm: 6px;
  --radius-md: 12px;
  --radius-lg: 20px;
  --radius-xl: 30px;
  --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

/* 重置 */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; font-size: 16px; }
body {
  font-family: -apple-system, BlinkMacSystemFont, "PingFang SC", "Microsoft YaHei", "Hiragino Sans GB", sans-serif;
  color: var(--text-primary);
  background: var(--bg-white);
  line-height: 1.7;
  overflow-x: hidden;
}
a { text-decoration: none; color: inherit; transition: var(--transition); }
img { max-width: 100%; height: auto; display: block; }
ul, ol { list-style: none; }
button { cursor: pointer; border: none; background: none; font-family: inherit; }

/* ========== 顶部公告栏 ========== */
.top-bar {
  background: linear-gradient(90deg, var(--dark) 0%, var(--dark-3) 100%);
  color: rgba(255,255,255,0.85);
  font-size: 13px;
  padding: 6px 0;
  text-align: center;
}
.top-bar a { color: var(--secondary); }
.top-bar a:hover { color: #fff; }

/* ========== 头部导航 ========== */
.site-header {
  background: var(--bg-white);
  box-shadow: var(--shadow-sm);
  position: sticky;
  top: 0;
  z-index: 1000;
  border-bottom: 2px solid var(--primary);
}
.header-inner {
  max-width: 1280px;
  margin: 0 auto;
  padding: 0 20px;
  display: flex;
  align-items: center;
  gap: 24px;
  height: 70px;
}
.site-logo {
  display: flex;
  align-items: center;
  gap: 10px;
  flex-shrink: 0;
}
.site-logo img {
  width: 42px;
  height: 42px;
  object-fit: contain;
}
.site-logo .logo-text {
  font-size: 22px;
  font-weight: 800;
  background: linear-gradient(135deg, var(--primary) 0%, var(--secondary) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  letter-spacing: 1px;
}
.site-logo .logo-sub {
  font-size: 11px;
  color: var(--text-light);
  display: block;
  line-height: 1;
  margin-top: 2px;
}

/* 主导航 */
.main-nav { flex: 1; }
.main-nav ul {
  display: flex;
  align-items: center;
  gap: 4px;
}
.main-nav ul li a {
  display: block;
  padding: 8px 14px;
  font-size: 14px;
  font-weight: 600;
  color: var(--text-primary);
  border-radius: var(--radius-sm);
  transition: var(--transition);
  white-space: nowrap;
}
.main-nav ul li a:hover,
.main-nav ul li a.active {
  color: var(--primary);
  background: rgba(232,69,60,0.08);
}

/* 头部右侧 */
.header-right {
  display: flex;
  align-items: center;
  gap: 12px;
  flex-shrink: 0;
}
.btn-login {
  padding: 7px 18px;
  border: 1.5px solid var(--primary);
  color: var(--primary);
  border-radius: var(--radius-xl);
  font-size: 13px;
  font-weight: 600;
  transition: var(--transition);
}
.btn-login:hover {
  background: var(--primary);
  color: #fff;
}
.btn-join {
  padding: 7px 18px;
  background: linear-gradient(135deg, var(--primary) 0%, var(--secondary) 100%);
  color: #fff;
  border-radius: var(--radius-xl);
  font-size: 13px;
  font-weight: 600;
  transition: var(--transition);
}
.btn-join:hover {
  transform: translateY(-1px);
  box-shadow: 0 4px 15px rgba(232,69,60,0.4);
}

/* ========== 搜索框 ========== */
.search-bar-wrap {
  background: var(--bg-light);
  padding: 12px 0;
  border-bottom: 1px solid var(--border);
}
.search-bar-inner {
  max-width: 1280px;
  margin: 0 auto;
  padding: 0 20px;
  display: flex;
  align-items: center;
  gap: 12px;
}
.search-form {
  display: flex;
  align-items: center;
  background: var(--bg-white);
  border: 1.5px solid var(--border);
  border-radius: var(--radius-xl);
  overflow: hidden;
  flex: 1;
  max-width: 600px;
  transition: var(--transition);
}
.search-form:focus-within {
  border-color: var(--primary);
  box-shadow: 0 0 0 3px rgba(232,69,60,0.12);
}
.search-form input {
  flex: 1;
  padding: 10px 18px;
  border: none;
  outline: none;
  font-size: 14px;
  background: transparent;
  color: var(--text-primary);
}
.search-form button {
  padding: 10px 20px;
  background: linear-gradient(135deg, var(--primary) 0%, var(--secondary) 100%);
  color: #fff;
  font-size: 14px;
  font-weight: 600;
  transition: var(--transition);
}
.search-form button:hover { opacity: 0.9; }
.search-hot-tags {
  display: flex;
  align-items: center;
  gap: 8px;
  flex-wrap: wrap;
}
.search-hot-tags span { font-size: 12px; color: var(--text-light); }
.search-hot-tags a {
  font-size: 12px;
  color: var(--text-secondary);
  padding: 3px 10px;
  background: var(--bg-white);
  border: 1px solid var(--border);
  border-radius: 20px;
  transition: var(--transition);
}
.search-hot-tags a:hover { color: var(--primary); border-color: var(--primary); }

/* ========== 面包屑 ========== */
.breadcrumb {
  max-width: 1280px;
  margin: 0 auto;
  padding: 10px 20px;
  font-size: 13px;
  color: var(--text-light);
}
.breadcrumb a { color: var(--text-light); }
.breadcrumb a:hover { color: var(--primary); }
.breadcrumb span { margin: 0 6px; }

/* ========== 通用容器 ========== */
.container {
  max-width: 1280px;
  margin: 0 auto;
  padding: 0 20px;
}
.section { padding: 60px 0; }
.section-sm { padding: 40px 0; }
.section-title {
  text-align: center;
  margin-bottom: 40px;
}
.section-title h2 {
  font-size: 32px;
  font-weight: 800;
  color: var(--dark);
  margin-bottom: 12px;
  position: relative;
  display: inline-block;
}
.section-title h2::after {
  content: '';
  position: absolute;
  bottom: -6px;
  left: 50%;
  transform: translateX(-50%);
  width: 60px;
  height: 3px;
  background: linear-gradient(90deg, var(--primary), var(--secondary));
  border-radius: 2px;
}
.section-title p {
  color: var(--text-secondary);
  font-size: 15px;
  margin-top: 16px;
}
.section-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 24px;
}
.section-header h2 {
  font-size: 22px;
  font-weight: 800;
  color: var(--dark);
  display: flex;
  align-items: center;
  gap: 8px;
}
.section-header h2::before {
  content: '';
  display: inline-block;
  width: 4px;
  height: 22px;
  background: linear-gradient(180deg, var(--primary), var(--secondary));
  border-radius: 2px;
}
.more-link {
  font-size: 13px;
  color: var(--text-light);
  display: flex;
  align-items: center;
  gap: 4px;
}
.more-link:hover { color: var(--primary); }

/* ========== Hero Banner ========== */
.hero-banner {
  position: relative;
  height: 520px;
  overflow: hidden;
  background: var(--dark);
}
.hero-banner img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  opacity: 0.75;
}
.hero-overlay {
  position: absolute;
  inset: 0;
  background: linear-gradient(135deg, rgba(26,26,46,0.85) 0%, rgba(232,69,60,0.3) 100%);
  display: flex;
  align-items: center;
}
.hero-content {
  max-width: 1280px;
  margin: 0 auto;
  padding: 0 20px;
  color: #fff;
}
.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  background: rgba(232,69,60,0.9);
  color: #fff;
  padding: 5px 14px;
  border-radius: 20px;
  font-size: 12px;
  font-weight: 600;
  margin-bottom: 16px;
  letter-spacing: 1px;
}
.hero-content h1 {
  font-size: 52px;
  font-weight: 900;
  line-height: 1.2;
  margin-bottom: 16px;
  text-shadow: 0 2px 20px rgba(0,0,0,0.3);
}
.hero-content h1 span { color: var(--secondary); }
.hero-content p {
  font-size: 18px;
  opacity: 0.9;
  margin-bottom: 28px;
  max-width: 560px;
  line-height: 1.6;
}
.hero-btns { display: flex; gap: 14px; flex-wrap: wrap; }
.btn-hero-primary {
  padding: 13px 32px;
  background: linear-gradient(135deg, var(--primary) 0%, var(--secondary) 100%);
  color: #fff;
  border-radius: var(--radius-xl);
  font-size: 15px;
  font-weight: 700;
  transition: var(--transition);
  display: flex;
  align-items: center;
  gap: 8px;
}
.btn-hero-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 25px rgba(232,69,60,0.5);
}
.btn-hero-secondary {
  padding: 13px 32px;
  background: rgba(255,255,255,0.15);
  backdrop-filter: blur(10px);
  color: #fff;
  border: 1.5px solid rgba(255,255,255,0.4);
  border-radius: var(--radius-xl);
  font-size: 15px;
  font-weight: 600;
  transition: var(--transition);
}
.btn-hero-secondary:hover {
  background: rgba(255,255,255,0.25);
}
.hero-stats {
  display: flex;
  gap: 32px;
  margin-top: 36px;
}
.hero-stat { text-align: center; }
.hero-stat .num {
  font-size: 28px;
  font-weight: 900;
  color: var(--secondary);
}
.hero-stat .label {
  font-size: 12px;
  opacity: 0.8;
  margin-top: 2px;
}

/* ========== 视频卡片 ========== */
.video-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 20px;
}
.video-card {
  background: var(--bg-white);
  border-radius: var(--radius-md);
  overflow: hidden;
  box-shadow: var(--shadow-sm);
  transition: var(--transition);
  cursor: pointer;
}
.video-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-lg);
}
.video-thumb {
  position: relative;
  aspect-ratio: 16/9;
  overflow: hidden;
  background: var(--dark);
}
.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);
  transition: var(--transition);
}
.video-card:hover .video-play-btn { background: rgba(0,0,0,0.35); }
.play-icon {
  width: 52px;
  height: 52px;
  background: rgba(255,255,255,0.95);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  opacity: 0;
  transform: scale(0.8);
  transition: var(--transition);
}
.video-card:hover .play-icon {
  opacity: 1;
  transform: scale(1);
}
.play-icon::after {
  content: '';
  border-left: 18px solid var(--primary);
  border-top: 11px solid transparent;
  border-bottom: 11px solid transparent;
  margin-left: 4px;
}
.video-duration {
  position: absolute;
  bottom: 8px;
  right: 8px;
  background: rgba(0,0,0,0.75);
  color: #fff;
  font-size: 11px;
  padding: 2px 7px;
  border-radius: 4px;
}
.video-tag {
  position: absolute;
  top: 8px;
  left: 8px;
  background: var(--primary);
  color: #fff;
  font-size: 11px;
  padding: 2px 8px;
  border-radius: 4px;
  font-weight: 600;
}
.video-info { padding: 14px; }
.video-info h3 {
  font-size: 14px;
  font-weight: 700;
  color: var(--text-primary);
  line-height: 1.4;
  margin-bottom: 8px;
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
}
.video-meta {
  display: flex;
  align-items: center;
  gap: 12px;
  font-size: 12px;
  color: var(--text-light);
}
.video-meta .author { display: flex; align-items: center; gap: 4px; }
.video-stats { display: flex; gap: 10px; }
.video-stats span { display: flex; align-items: center; gap: 3px; }

/* ========== 栏目标签 ========== */
.category-tabs {
  display: flex;
  gap: 8px;
  flex-wrap: wrap;
  margin-bottom: 24px;
}
.cat-tab {
  padding: 7px 18px;
  border-radius: var(--radius-xl);
  font-size: 13px;
  font-weight: 600;
  border: 1.5px solid var(--border);
  color: var(--text-secondary);
  transition: var(--transition);
  cursor: pointer;
}
.cat-tab:hover,
.cat-tab.active {
  background: var(--primary);
  border-color: var(--primary);
  color: #fff;
}

/* ========== 图文卡片 ========== */
.card-grid-3 {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}
.card-grid-4 {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 20px;
}
.content-card {
  background: var(--bg-white);
  border-radius: var(--radius-md);
  overflow: hidden;
  box-shadow: var(--shadow-sm);
  transition: var(--transition);
}
.content-card:hover {
  transform: translateY(-3px);
  box-shadow: var(--shadow-md);
}
.content-card .card-img {
  aspect-ratio: 4/3;
  overflow: hidden;
}
.content-card .card-img img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform 0.4s ease;
}
.content-card:hover .card-img img { transform: scale(1.05); }
.content-card .card-body { padding: 16px; }
.content-card .card-tag {
  display: inline-block;
  font-size: 11px;
  color: var(--primary);
  background: rgba(232,69,60,0.1);
  padding: 2px 8px;
  border-radius: 4px;
  margin-bottom: 8px;
  font-weight: 600;
}
.content-card h3 {
  font-size: 15px;
  font-weight: 700;
  color: var(--text-primary);
  margin-bottom: 8px;
  line-height: 1.4;
}
.content-card p {
  font-size: 13px;
  color: var(--text-secondary);
  line-height: 1.6;
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

/* ========== 专家卡片 ========== */
.expert-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 24px;
}
.expert-card {
  background: var(--bg-white);
  border-radius: var(--radius-md);
  padding: 28px 20px;
  text-align: center;
  box-shadow: var(--shadow-sm);
  transition: var(--transition);
  border: 1px solid var(--border);
}
.expert-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-md);
  border-color: var(--primary);
}
.expert-avatar {
  width: 90px;
  height: 90px;
  border-radius: 50%;
  object-fit: cover;
  margin: 0 auto 14px;
  border: 3px solid var(--primary);
}
.expert-card h3 { font-size: 16px; font-weight: 800; color: var(--dark); margin-bottom: 4px; }
.expert-card .role {
  font-size: 12px;
  color: var(--primary);
  font-weight: 600;
  margin-bottom: 10px;
}
.expert-card p { font-size: 13px; color: var(--text-secondary); line-height: 1.6; margin-bottom: 14px; }
.expert-awards { display: flex; flex-wrap: wrap; gap: 4px; justify-content: center; margin-bottom: 14px; }
.expert-awards span {
  font-size: 11px;
  background: rgba(245,166,35,0.15);
  color: var(--secondary-dark);
  padding: 2px 8px;
  border-radius: 4px;
}
.expert-btns { display: flex; gap: 8px; justify-content: center; }
.btn-sm {
  padding: 6px 14px;
  border-radius: 20px;
  font-size: 12px;
  font-weight: 600;
  transition: var(--transition);
}
.btn-sm.primary { background: var(--primary); color: #fff; }
.btn-sm.primary:hover { background: var(--primary-dark); }
.btn-sm.outline { border: 1.5px solid var(--border); color: var(--text-secondary); }
.btn-sm.outline:hover { border-color: var(--primary); color: var(--primary); }

/* ========== 用户评价 ========== */
.review-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 20px;
}
.review-card {
  background: var(--bg-white);
  border-radius: var(--radius-md);
  padding: 22px;
  box-shadow: var(--shadow-sm);
  border: 1px solid var(--border);
  transition: var(--transition);
}
.review-card:hover { box-shadow: var(--shadow-md); }
.review-header { display: flex; align-items: center; gap: 12px; margin-bottom: 12px; }
.review-avatar {
  width: 44px;
  height: 44px;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--primary), var(--secondary));
  display: flex;
  align-items: center;
  justify-content: center;
  color: #fff;
  font-size: 16px;
  font-weight: 800;
  flex-shrink: 0;
}
.review-user h4 { font-size: 14px; font-weight: 700; color: var(--dark); }
.review-user span { font-size: 12px; color: var(--text-light); }
.review-stars { color: var(--secondary); font-size: 14px; margin-bottom: 8px; }
.review-card p { font-size: 13px; color: var(--text-secondary); line-height: 1.7; }
.review-date { font-size: 11px; color: var(--text-light); margin-top: 10px; }

/* ========== FAQ ========== */
.faq-list { max-width: 860px; margin: 0 auto; }
.faq-item {
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  margin-bottom: 12px;
  overflow: hidden;
  transition: var(--transition);
}
.faq-item:hover { border-color: var(--primary); }
.faq-question {
  padding: 18px 22px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  cursor: pointer;
  font-size: 15px;
  font-weight: 700;
  color: var(--dark);
  background: var(--bg-white);
  transition: var(--transition);
}
.faq-question:hover { color: var(--primary); }
.faq-icon {
  width: 24px;
  height: 24px;
  border-radius: 50%;
  background: var(--bg-light);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 16px;
  flex-shrink: 0;
  transition: var(--transition);
}
.faq-item.open .faq-icon { background: var(--primary); color: #fff; transform: rotate(45deg); }
.faq-answer {
  padding: 0 22px;
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.3s ease, padding 0.3s ease;
  font-size: 14px;
  color: var(--text-secondary);
  line-height: 1.8;
}
.faq-item.open .faq-answer { max-height: 300px; padding: 0 22px 18px; }

/* ========== 合作品牌 ========== */
.partner-logos {
  display: flex;
  align-items: center;
  justify-content: center;
  flex-wrap: wrap;
  gap: 24px;
}
.partner-logo {
  padding: 14px 24px;
  background: var(--bg-white);
  border: 1.5px solid var(--border);
  border-radius: var(--radius-md);
  font-size: 15px;
  font-weight: 700;
  color: var(--text-secondary);
  transition: var(--transition);
  min-width: 120px;
  text-align: center;
}
.partner-logo:hover { border-color: var(--primary); color: var(--primary); transform: translateY(-2px); }

/* ========== 联系我们 ========== */
.contact-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 40px;
  align-items: start;
}
.contact-info h3 { font-size: 20px; font-weight: 800; color: var(--dark); margin-bottom: 20px; }
.contact-item {
  display: flex;
  align-items: flex-start;
  gap: 14px;
  margin-bottom: 16px;
}
.contact-icon {
  width: 42px;
  height: 42px;
  border-radius: var(--radius-sm);
  background: linear-gradient(135deg, var(--primary), var(--secondary));
  display: flex;
  align-items: center;
  justify-content: center;
  color: #fff;
  font-size: 18px;
  flex-shrink: 0;
}
.contact-item h4 { font-size: 14px; font-weight: 700; color: var(--dark); margin-bottom: 2px; }
.contact-item p { font-size: 13px; color: var(--text-secondary); }
.qr-group { display: flex; gap: 24px; }
.qr-item { text-align: center; }
.qr-item img { width: 130px; height: 130px; object-fit: cover; border-radius: var(--radius-sm); margin-bottom: 8px; }
.qr-item span { font-size: 12px; color: var(--text-secondary); }

/* ========== 社交分享 ========== */
.share-bar {
  background: var(--bg-light);
  padding: 16px 0;
  border-top: 1px solid var(--border);
}
.share-inner {
  max-width: 1280px;
  margin: 0 auto;
  padding: 0 20px;
  display: flex;
  align-items: center;
  gap: 16px;
}
.share-label { font-size: 13px; color: var(--text-secondary); font-weight: 600; }
.share-btns { display: flex; gap: 8px; }
.share-btn {
  padding: 6px 16px;
  border-radius: 20px;
  font-size: 12px;
  font-weight: 600;
  transition: var(--transition);
  border: 1.5px solid var(--border);
  color: var(--text-secondary);
}
.share-btn:hover { transform: translateY(-1px); }
.share-btn.weixin:hover { background: #07C160; border-color: #07C160; color: #fff; }
.share-btn.weibo:hover { background: #E6162D; border-color: #E6162D; color: #fff; }
.share-btn.douyin:hover { background: #000; border-color: #000; color: #fff; }
.share-btn.bilibili:hover { background: #00A1D6; border-color: #00A1D6; color: #fff; }

/* ========== 页脚 ========== */
.site-footer {
  background: var(--dark);
  color: rgba(255,255,255,0.75);
  padding: 60px 0 0;
}
.footer-grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1fr;
  gap: 40px;
  margin-bottom: 40px;
}
.footer-brand .logo-wrap {
  display: flex;
  align-items: center;
  gap: 10px;
  margin-bottom: 16px;
}
.footer-brand .logo-wrap img { width: 36px; height: 36px; object-fit: contain; }
.footer-brand .logo-wrap span {
  font-size: 20px;
  font-weight: 800;
  background: linear-gradient(135deg, var(--primary), var(--secondary));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}
.footer-brand p { font-size: 13px; line-height: 1.8; margin-bottom: 20px; }
.footer-social { display: flex; gap: 10px; }
.social-icon {
  width: 36px;
  height: 36px;
  border-radius: 50%;
  background: rgba(255,255,255,0.1);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 14px;
  transition: var(--transition);
}
.social-icon:hover { background: var(--primary); }
.footer-col h4 {
  font-size: 14px;
  font-weight: 700;
  color: #fff;
  margin-bottom: 16px;
  padding-bottom: 8px;
  border-bottom: 1px solid rgba(255,255,255,0.1);
}
.footer-col ul li { margin-bottom: 8px; }
.footer-col ul li a { font-size: 13px; color: rgba(255,255,255,0.6); transition: var(--transition); }
.footer-col ul li a:hover { color: var(--secondary); padding-left: 4px; }
.footer-bottom {
  border-top: 1px solid rgba(255,255,255,0.1);
  padding: 20px 0;
  display: flex;
  align-items: center;
  justify-content: space-between;
  font-size: 12px;
  color: rgba(255,255,255,0.45);
}
.footer-bottom a { color: rgba(255,255,255,0.45); }
.footer-bottom a:hover { color: var(--secondary); }
.footer-links { display: flex; gap: 16px; }

/* ========== 特色区块 ========== */
.feature-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 24px;
}
.feature-card {
  text-align: center;
  padding: 32px 20px;
  background: var(--bg-white);
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-sm);
  border: 1px solid var(--border);
  transition: var(--transition);
}
.feature-card:hover {
  border-color: var(--primary);
  transform: translateY(-4px);
  box-shadow: var(--shadow-md);
}
.feature-icon {
  width: 64px;
  height: 64px;
  border-radius: var(--radius-md);
  background: linear-gradient(135deg, var(--primary), var(--secondary));
  display: flex;
  align-items: center;
  justify-content: center;
  margin: 0 auto 16px;
  font-size: 28px;
}
.feature-card h3 { font-size: 16px; font-weight: 800; color: var(--dark); margin-bottom: 8px; }
.feature-card p { font-size: 13px; color: var(--text-secondary); line-height: 1.7; }

/* ========== 直播区 ========== */
.live-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 20px;
}
.live-card {
  border-radius: var(--radius-md);
  overflow: hidden;
  position: relative;
  aspect-ratio: 3/4;
  cursor: pointer;
}
.live-card img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform 0.4s ease;
}
.live-card:hover img { transform: scale(1.05); }
.live-overlay {
  position: absolute;
  inset: 0;
  background: linear-gradient(to top, rgba(0,0,0,0.7) 0%, transparent 50%);
}
.live-badge {
  position: absolute;
  top: 12px;
  left: 12px;
  background: #FF0000;
  color: #fff;
  font-size: 11px;
  font-weight: 700;
  padding: 3px 10px;
  border-radius: 4px;
  display: flex;
  align-items: center;
  gap: 4px;
}
.live-badge::before {
  content: '';
  width: 6px;
  height: 6px;
  background: #fff;
  border-radius: 50%;
  animation: pulse 1.5s infinite;
}
@keyframes pulse {
  0%, 100% { opacity: 1; }
  50% { opacity: 0.3; }
}
.live-info {
  position: absolute;
  bottom: 0;
  left: 0;
  right: 0;
  padding: 16px;
  color: #fff;
}
.live-info h3 { font-size: 14px; font-weight: 700; margin-bottom: 4px; }
.live-info p { font-size: 12px; opacity: 0.8; }
.live-viewers { font-size: 11px; color: rgba(255,255,255,0.7); }

/* ========== AI专区 ========== */
.ai-section { background: linear-gradient(135deg, var(--dark) 0%, var(--dark-3) 100%); }
.ai-section .section-title h2 { color: #fff; }
.ai-section .section-title h2::after { background: linear-gradient(90deg, var(--primary), var(--secondary)); }
.ai-section .section-title p { color: rgba(255,255,255,0.7); }
.ai-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}
.ai-card {
  background: rgba(255,255,255,0.08);
  border: 1px solid rgba(255,255,255,0.12);
  border-radius: var(--radius-md);
  padding: 28px;
  transition: var(--transition);
  backdrop-filter: blur(10px);
}
.ai-card:hover {
  background: rgba(255,255,255,0.12);
  border-color: var(--primary);
  transform: translateY(-3px);
}
.ai-card-icon {
  font-size: 36px;
  margin-bottom: 16px;
}
.ai-card h3 { font-size: 17px; font-weight: 800; color: #fff; margin-bottom: 10px; }
.ai-card p { font-size: 13px; color: rgba(255,255,255,0.65); line-height: 1.7; margin-bottom: 16px; }
.ai-tag {
  display: inline-block;
  font-size: 11px;
  padding: 3px 10px;
  border-radius: 20px;
  background: rgba(232,69,60,0.3);
  color: var(--primary-light);
  font-weight: 600;
}

/* ========== 加入社区 ========== */
.join-section {
  background: linear-gradient(135deg, var(--primary) 0%, var(--secondary) 100%);
  color: #fff;
  text-align: center;
  padding: 70px 0;
}
.join-section h2 { font-size: 36px; font-weight: 900; margin-bottom: 14px; }
.join-section p { font-size: 16px; opacity: 0.9; margin-bottom: 32px; }
.join-steps {
  display: flex;
  justify-content: center;
  gap: 32px;
  margin-bottom: 36px;
  flex-wrap: wrap;
}
.join-step {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 8px;
}
.step-num {
  width: 44px;
  height: 44px;
  border-radius: 50%;
  background: rgba(255,255,255,0.25);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 18px;
  font-weight: 900;
}
.join-step span { font-size: 13px; opacity: 0.9; }
.btn-join-big {
  display: inline-block;
  padding: 14px 40px;
  background: #fff;
  color: var(--primary);
  border-radius: var(--radius-xl);
  font-size: 16px;
  font-weight: 800;
  transition: var(--transition);
}
.btn-join-big:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 30px rgba(0,0,0,0.2);
}

/* ========== 内页通用 ========== */
.page-hero {
  background: linear-gradient(135deg, var(--dark) 0%, var(--dark-3) 100%);
  color: #fff;
  padding: 60px 0 50px;
  text-align: center;
}
.page-hero h1 { font-size: 38px; font-weight: 900; margin-bottom: 12px; }
.page-hero p { font-size: 15px; opacity: 0.8; max-width: 600px; margin: 0 auto; }
.page-content { padding: 50px 0; }
.page-intro {
  background: var(--bg-light);
  border-radius: var(--radius-md);
  padding: 28px;
  margin-bottom: 36px;
  border-left: 4px solid var(--primary);
}
.page-intro p { font-size: 15px; color: var(--text-secondary); line-height: 1.8; }

/* ========== 响应式 ========== */
.hamburger {
  display: none;
  flex-direction: column;
  gap: 5px;
  cursor: pointer;
  padding: 4px;
}
.hamburger span {
  display: block;
  width: 24px;
  height: 2px;
  background: var(--text-primary);
  border-radius: 2px;
  transition: var(--transition);
}

@media (max-width: 1024px) {
  .video-grid { grid-template-columns: repeat(3, 1fr); }
  .expert-grid { grid-template-columns: repeat(2, 1fr); }
  .review-grid { grid-template-columns: repeat(2, 1fr); }
  .footer-grid { grid-template-columns: 1fr 1fr; }
  .hero-content h1 { font-size: 40px; }
}

@media (max-width: 768px) {
  .hamburger { display: flex; }
  .main-nav {
    display: none;
    position: absolute;
    top: 70px;
    left: 0;
    right: 0;
    background: var(--bg-white);
    box-shadow: var(--shadow-md);
    padding: 16px;
    z-index: 999;
  }
  .main-nav.open { display: block; }
  .main-nav ul { flex-direction: column; gap: 4px; }
  .main-nav ul li a { padding: 10px 16px; }
  .header-right .btn-login { display: none; }
  .video-grid { grid-template-columns: repeat(2, 1fr); }
  .card-grid-3 { grid-template-columns: 1fr; }
  .card-grid-4 { grid-template-columns: repeat(2, 1fr); }
  .feature-grid { grid-template-columns: repeat(2, 1fr); }
  .expert-grid { grid-template-columns: 1fr; }
  .live-grid { grid-template-columns: repeat(2, 1fr); }
  .ai-grid { grid-template-columns: 1fr; }
  .contact-grid { grid-template-columns: 1fr; }
  .footer-grid { grid-template-columns: 1fr; }
  .hero-banner { height: 380px; }
  .hero-content h1 { font-size: 28px; }
  .hero-content p { font-size: 14px; }
  .hero-stats { gap: 16px; }
  .hero-stat .num { font-size: 22px; }
  .join-steps { gap: 16px; }
  .search-hot-tags { display: none; }
  .footer-bottom { flex-direction: column; gap: 8px; text-align: center; }
}

@media (max-width: 480px) {
  .video-grid { grid-template-columns: 1fr; }
  .card-grid-4 { grid-template-columns: 1fr; }
  .feature-grid { grid-template-columns: 1fr; }
  .live-grid { grid-template-columns: 1fr; }
  .review-grid { grid-template-columns: 1fr; }
  .hero-btns { flex-direction: column; }
  .section-title h2 { font-size: 24px; }
}

/* ========== 动画 ========== */
@keyframes fadeInUp {
  from { opacity: 0; transform: translateY(20px); }
  to { opacity: 1; transform: translateY(0); }
}
.fade-in { animation: fadeInUp 0.6s ease forwards; }

/* ========== 懒加载占位 ========== */
img[data-src] { background: var(--bg-light); }

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

/* ========== 更新时间 ========== */
.update-time { font-size: 12px; color: var(--text-light); }