/* ===== 抖音风视频社区 - 主样式表 ===== */
:root {
  --primary: #1a7a3c;
  --primary-light: #2ea855;
  --primary-dark: #0d4a24;
  --accent: #5dce7a;
  --bg-dark: #0a120d;
  --bg-card: #111a14;
  --bg-card2: #162019;
  --text-white: #f0f7f2;
  --text-muted: #7a9b82;
  --border: rgba(26,122,60,0.22);
  --shadow: 0 8px 32px rgba(0,0,0,0.5);
  --radius: 12px;
  --radius-sm: 8px;
  --transition: 0.22s ease;
}

*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

html { scroll-behavior: smooth; }

body {
  font-family: "PingFang SC", "Microsoft YaHei", "Hiragino Sans GB", sans-serif;
  background: var(--bg-dark);
  color: var(--text-white);
  line-height: 1.65;
  font-size: 16px;
}

a { color: inherit; text-decoration: none; }
img { max-width: 100%; height: auto; display: block; }
ul, ol { list-style: none; }

/* ===== 干扰标签隐藏 ===== */
.seo-noise {
  display: none !important;
  position: absolute;
  width: 0; height: 0;
  overflow: hidden;
  visibility: hidden;
  pointer-events: none;
}

/* ===== 头部 ===== */
#site-header {
  position: sticky; top: 0; z-index: 1000;
  background: rgba(10,18,13,0.96);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border);
}

.header-inner {
  max-width: 1280px; margin: 0 auto;
  padding: 0 20px; height: 64px;
  display: flex; align-items: center; gap: 24px;
}

.site-logo {
  display: flex; align-items: center; gap: 10px;
  font-size: 1.5rem; font-weight: 900; color: var(--text-white);
  flex-shrink: 0;
}

.site-logo img { width: 40px; height: 40px; border-radius: 8px; object-fit: cover; }
.site-logo span span { color: var(--accent); }

.nav-toggle {
  display: none; flex-direction: column; gap: 5px;
  background: none; border: none; cursor: pointer; padding: 4px; margin-left: auto;
}

.nav-toggle span {
  display: block; width: 22px; height: 2px;
  background: var(--text-white); border-radius: 2px;
  transition: all var(--transition);
}

#main-nav {
  display: flex; align-items: center; gap: 4px;
  margin-left: auto; flex-wrap: wrap;
}

#main-nav a {
  padding: 7px 14px; border-radius: 20px;
  font-size: 0.9rem; font-weight: 600; color: var(--text-muted);
  transition: all var(--transition); white-space: nowrap;
}

#main-nav a:hover,
#main-nav a.active { color: var(--accent); background: rgba(26,122,60,0.15); }

/* ===== 搜索框 ===== */
#search-bar-wrap {
  background: var(--bg-card); border-bottom: 1px solid var(--border);
  padding: 10px 20px;
}

.search-inner {
  max-width: 1280px; margin: 0 auto;
}

#search-form {
  display: flex; gap: 8px; max-width: 640px; margin: 0 auto;
}

#site-search {
  flex: 1; background: var(--bg-card2); border: 1px solid var(--border);
  border-radius: 24px; padding: 9px 18px; color: var(--text-white);
  font-size: 0.93rem; outline: none; transition: border-color var(--transition);
}

#site-search:focus { border-color: var(--primary-light); }
#site-search::placeholder { color: var(--text-muted); }

.search-btn {
  background: var(--primary); color: #fff; border: none;
  border-radius: 24px; padding: 8px 22px; cursor: pointer;
  font-size: 0.95rem; font-weight: 600; transition: background var(--transition);
}

.search-btn:hover { background: var(--primary-light); }

/* ===== 面包屑 ===== */
.breadcrumb {
  max-width: 1280px; margin: 0 auto;
  padding: 10px 20px; font-size: 0.85rem; color: var(--text-muted);
}

.breadcrumb a { color: var(--text-muted); }
.breadcrumb a:hover { color: var(--accent); }
.breadcrumb span { margin: 0 6px; }

/* ===== HERO BANNER ===== */
#hero {
  position: relative; min-height: 520px;
  display: flex; align-items: center; justify-content: center;
  overflow: hidden;
}

.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-content {
  position: relative; z-index: 1;
  text-align: center; padding: 60px 20px;
  max-width: 860px;
}

.hero-content h1 {
  font-size: clamp(2rem, 5vw, 3.6rem);
  font-weight: 900; color: #fff;
  text-shadow: 0 2px 16px rgba(0,0,0,0.7);
  margin-bottom: 16px; line-height: 1.2;
}

.hero-content h1 .brand { color: var(--accent); }

.hero-content p {
  font-size: clamp(1rem, 2vw, 1.2rem);
  color: rgba(255,255,255,0.88); margin-bottom: 32px;
  max-width: 640px; margin-left: auto; margin-right: auto;
}

.hero-btns { display: flex; gap: 16px; justify-content: center; flex-wrap: wrap; }

.btn-primary {
  background: var(--primary); color: #fff;
  padding: 13px 32px; border-radius: 32px;
  font-size: 1rem; font-weight: 700;
  transition: all var(--transition); border: 2px solid var(--primary);
  display: inline-flex; align-items: center; gap: 8px;
}

.btn-primary:hover { background: var(--primary-light); border-color: var(--primary-light); color: #fff; transform: translateY(-2px); }

.btn-outline {
  background: transparent; color: #fff;
  padding: 13px 32px; border-radius: 32px;
  font-size: 1rem; font-weight: 700;
  border: 2px solid rgba(255,255,255,0.6);
  transition: all var(--transition);
  display: inline-flex; align-items: center; gap: 8px;
}

.btn-outline:hover { background: rgba(255,255,255,0.15); color: #fff; border-color: #fff; }

/* ===== 通用 section ===== */
.section { padding: 72px 20px; }
.section-alt { background: var(--bg-card); }
.section-dark { background: var(--bg-card2); }

.container { max-width: 1280px; margin: 0 auto; }

.section-header { text-align: center; margin-bottom: 48px; }

.section-header h2 {
  font-size: clamp(1.6rem, 3vw, 2.4rem);
  font-weight: 800; color: var(--text-white);
  margin-bottom: 12px;
}

.section-header h2 .brand { color: var(--accent); }

.section-header p { color: var(--text-muted); font-size: 1.05rem; max-width: 640px; margin: 0 auto; }

.divider {
  width: 60px; height: 4px;
  background: linear-gradient(90deg, var(--primary), var(--accent));
  border-radius: 2px; margin: 16px auto 0;
}

/* ===== 媒体子导航 ===== */
.media-sub-nav {
  display: flex; flex-wrap: wrap; gap: 12px;
  justify-content: center; margin-bottom: 8px;
}

.media-sub-nav h4 {
  font-size: 0.88rem; font-weight: 600;
}

.media-sub-nav h4 a {
  color: var(--text-muted);
  padding: 5px 14px; border-radius: 16px;
  border: 1px solid var(--border);
  transition: all var(--transition);
  display: block;
}

.media-sub-nav h4 a:hover {
  color: var(--accent); border-color: var(--primary);
  background: rgba(26,122,60,0.1);
}

/* ===== 视频卡片 ===== */
.video-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 24px;
}

.video-card {
  background: var(--bg-card2); border-radius: var(--radius);
  overflow: hidden; transition: transform var(--transition), box-shadow var(--transition);
  border: 1px solid var(--border); cursor: pointer;
}

.video-card:hover { transform: translateY(-6px); box-shadow: var(--shadow); }

.video-thumb {
  position: relative; aspect-ratio: 16/9; overflow: hidden;
  background: #0a1a0f;
}

.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); }

.play-btn {
  position: absolute; inset: 0;
  display: flex; align-items: center; justify-content: center;
  background: rgba(0,0,0,0.3);
  opacity: 0; transition: opacity var(--transition);
}

.video-card:hover .play-btn { opacity: 1; }

.play-icon {
  width: 56px; height: 56px; border-radius: 50%;
  background: rgba(255,255,255,0.92);
  display: flex; align-items: center; justify-content: center;
  box-shadow: 0 4px 20px rgba(0,0,0,0.4);
  transition: transform var(--transition);
}

.video-card:hover .play-icon { transform: scale(1.1); }

.play-icon::after {
  content: '';
  border-left: 18px solid var(--primary-dark);
  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: 0.78rem; padding: 2px 7px; border-radius: 4px;
}

.video-tag {
  position: absolute; top: 8px; left: 8px;
  background: var(--primary); color: #fff;
  font-size: 0.72rem; padding: 2px 8px; border-radius: 4px; font-weight: 600;
}

.video-info { padding: 14px 16px; }

.video-info h3 {
  font-size: 0.97rem; font-weight: 700; color: var(--text-white);
  margin-bottom: 6px; line-height: 1.4;
  display: -webkit-box; -webkit-line-clamp: 2; -webkit-box-orient: vertical; overflow: hidden;
}

.video-author {
  color: var(--text-muted); font-size: 0.82rem; margin-bottom: 6px;
}

.video-meta { display: flex; gap: 12px; font-size: 0.82rem; color: var(--text-muted); flex-wrap: wrap; }
.video-meta span { display: flex; align-items: center; gap: 4px; }

/* ===== 统计数据 ===== */
.stats-bar {
  background: linear-gradient(135deg, var(--primary-dark), var(--bg-card2));
  padding: 40px 20px; border-top: 1px solid var(--border); border-bottom: 1px solid var(--border);
}

.stats-grid {
  max-width: 1280px; margin: 0 auto;
  display: grid; grid-template-columns: repeat(auto-fit, minmax(160px, 1fr));
  gap: 24px; text-align: center;
}

.stat-item h3 { font-size: 2.4rem; font-weight: 900; color: var(--accent); }
.stat-item p { font-size: 0.9rem; color: var(--text-muted); margin-top: 4px; }

/* ===== 专家卡片 ===== */
.expert-grid {
  display: grid; grid-template-columns: repeat(auto-fill, minmax(240px, 1fr));
  gap: 28px;
}

.expert-card {
  background: var(--bg-card2); border-radius: var(--radius);
  padding: 28px 20px; text-align: center;
  border: 1px solid var(--border); transition: transform var(--transition), box-shadow var(--transition);
}

.expert-card:hover { transform: translateY(-4px); box-shadow: var(--shadow); }

.expert-avatar {
  width: 90px; height: 90px; border-radius: 50%;
  object-fit: cover; margin: 0 auto 16px;
  border: 3px solid var(--primary);
}

.expert-card h3 { font-size: 1.1rem; font-weight: 700; color: var(--text-white); margin-bottom: 4px; }
.expert-card .role { font-size: 0.85rem; color: var(--accent); margin-bottom: 10px; }
.expert-card p { font-size: 0.88rem; color: var(--text-muted); margin-bottom: 14px; }

.expert-btns { display: flex; gap: 8px; justify-content: center; flex-wrap: wrap; }

.btn-sm {
  padding: 6px 14px; border-radius: 20px; font-size: 0.82rem; font-weight: 600;
  border: 1px solid var(--primary); color: var(--primary-light);
  transition: all var(--transition);
}

.btn-sm:hover { background: var(--primary); color: #fff; }

/* ===== FAQ ===== */
.faq-list { max-width: 800px; margin: 0 auto; }

.faq-item {
  background: var(--bg-card2); border-radius: var(--radius);
  border: 1px solid var(--border); margin-bottom: 12px; overflow: hidden;
}

.faq-q {
  padding: 18px 20px; cursor: pointer;
  display: flex; justify-content: space-between; align-items: center;
  font-weight: 600; color: var(--text-white); font-size: 0.97rem;
  transition: background var(--transition);
}

.faq-q:hover { background: rgba(26,122,60,0.15); }

.faq-q .arrow {
  width: 20px; height: 20px; border-radius: 50%;
  background: var(--primary); display: flex; align-items: center; justify-content: center;
  flex-shrink: 0; transition: transform var(--transition);
  font-size: 0.8rem; color: #fff;
}

.faq-item.open .faq-q .arrow { transform: rotate(180deg); }

.faq-a {
  max-height: 0; overflow: hidden;
  transition: max-height 0.35s ease, padding 0.3s ease;
  padding: 0 20px; color: var(--text-muted); font-size: 0.93rem;
}

.faq-item.open .faq-a { max-height: 300px; padding: 0 20px 18px; }

/* ===== 评价 ===== */
.review-grid {
  display: grid; grid-template-columns: repeat(auto-fill, minmax(260px, 1fr));
  gap: 24px;
}

.review-card {
  background: var(--bg-card2); border-radius: var(--radius);
  padding: 24px; border: 1px solid var(--border);
  transition: transform var(--transition);
}

.review-card:hover { transform: translateY(-3px); }

.review-header { display: flex; align-items: center; gap: 12px; margin-bottom: 12px; }

.review-avatar {
  width: 44px; height: 44px; border-radius: 50%;
  background: var(--primary); display: flex; align-items: center; justify-content: center;
  font-size: 1.1rem; font-weight: 700; color: #fff; flex-shrink: 0;
}

.review-name { font-weight: 700; color: var(--text-white); font-size: 0.95rem; }
.review-date { font-size: 0.78rem; color: var(--text-muted); }

.stars { color: var(--accent); font-size: 0.9rem; margin-bottom: 10px; }
.review-text { font-size: 0.9rem; color: var(--text-muted); line-height: 1.6; }

/* ===== 合作品牌 ===== */
.brand-logos {
  display: flex; flex-wrap: wrap; gap: 20px;
  justify-content: center; align-items: center;
}

.brand-logo-item {
  background: var(--bg-card2); border: 1px solid var(--border);
  border-radius: var(--radius); padding: 16px 28px;
  font-size: 1rem; font-weight: 700; color: var(--text-muted);
  transition: all var(--transition);
}

.brand-logo-item:hover { border-color: var(--primary); color: var(--primary-light); background: rgba(26,122,60,0.1); }

/* ===== 社交分享 ===== */
.share-bar {
  display: flex; gap: 12px; flex-wrap: wrap; justify-content: center;
  padding: 24px 0;
}

.share-btn {
  padding: 10px 20px; border-radius: 24px; font-size: 0.9rem; font-weight: 600;
  border: none; cursor: pointer; transition: all var(--transition);
  display: flex; align-items: center; gap: 6px;
}

.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 { opacity: 0.85; transform: translateY(-2px); }

/* ===== 联系 ===== */
.contact-grid {
  display: grid; grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 28px;
}

.contact-card {
  background: var(--bg-card2); border-radius: var(--radius);
  padding: 28px; border: 1px solid var(--border);
}

.contact-card h3 { font-size: 1.1rem; font-weight: 700; color: var(--text-white); margin-bottom: 16px; }
.contact-card p { font-size: 0.92rem; color: var(--text-muted); margin-bottom: 8px; }
.contact-card strong { color: var(--text-white); }
.contact-card address { font-style: normal; }
.contact-card address a { color: var(--text-muted); }
.contact-card address a:hover { color: var(--accent); }

.qr-wrap { text-align: center; }

.qr-img {
  width: 140px; height: 140px; border-radius: 10px;
  object-fit: cover; margin: 0 auto 10px;
  border: 2px solid var(--border);
}

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

/* ===== 底部 ===== */
#site-footer {
  background: #080f0a; border-top: 1px solid var(--border);
  padding: 48px 20px 24px;
}

.footer-inner {
  max-width: 1280px; margin: 0 auto;
  display: grid; grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 36px; margin-bottom: 36px;
}

.footer-col h4 { font-size: 1rem; font-weight: 700; color: var(--text-white); margin-bottom: 14px; }
.footer-col a { display: block; font-size: 0.88rem; color: var(--text-muted); margin-bottom: 7px; }
.footer-col a:hover { color: var(--primary-light); }
.footer-col p { font-size: 0.85rem; color: var(--text-muted); line-height: 1.7; }

.footer-bottom {
  max-width: 1280px; margin: 0 auto;
  border-top: 1px solid var(--border); padding-top: 20px;
  display: flex; justify-content: space-between; align-items: center;
  flex-wrap: wrap; gap: 12px; font-size: 0.83rem; color: var(--text-muted);
}

.footer-logo { font-size: 1.1rem; font-weight: 800; color: var(--text-white); }
.footer-logo span { color: var(--accent); }

/* ===== 模块标签 ===== */
.tag-list { display: flex; flex-wrap: wrap; gap: 8px; margin-top: 12px; }

.tag {
  background: rgba(26,122,60,0.2); border: 1px solid var(--border);
  border-radius: 20px; padding: 4px 12px; font-size: 0.8rem; color: var(--primary-light);
}

/* ===== AI模块 ===== */
.ai-feature-grid {
  display: grid; grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
  gap: 24px;
}

.ai-card {
  background: linear-gradient(135deg, var(--bg-card2), rgba(26,122,60,0.08));
  border-radius: var(--radius); padding: 28px;
  border: 1px solid var(--border); transition: all var(--transition);
}

.ai-card:hover { border-color: var(--primary); transform: translateY(-3px); }

.ai-icon {
  width: 52px; height: 52px; border-radius: 12px;
  background: linear-gradient(135deg, var(--primary), var(--accent));
  display: flex; align-items: center; justify-content: center;
  font-size: 1.5rem; margin-bottom: 16px;
}

.ai-card h3 { font-size: 1.05rem; font-weight: 700; color: var(--text-white); margin-bottom: 8px; }
.ai-card p { font-size: 0.9rem; color: var(--text-muted); }

/* ===== 内页 banner ===== */
.inner-banner {
  background: linear-gradient(135deg, var(--bg-card2), var(--primary-dark));
  padding: 56px 20px; text-align: center;
  border-bottom: 1px solid var(--border);
}

.inner-banner h1 { font-size: clamp(1.8rem, 4vw, 2.8rem); font-weight: 900; color: #fff; margin-bottom: 10px; }
.inner-banner p { color: var(--text-muted); font-size: 1rem; max-width: 560px; margin: 0 auto; }

/* ===== 步骤 ===== */
.steps-grid {
  display: grid; grid-template-columns: repeat(auto-fill, minmax(220px, 1fr));
  gap: 24px;
}

.step-card {
  background: var(--bg-card2); border-radius: var(--radius);
  padding: 28px 20px; text-align: center; border: 1px solid var(--border);
}

.step-num {
  width: 44px; height: 44px; border-radius: 50%;
  background: var(--primary); color: #fff;
  font-size: 1.2rem; font-weight: 800;
  display: flex; align-items: center; justify-content: center;
  margin: 0 auto 14px;
}

.step-card h3 { font-size: 1rem; font-weight: 700; color: var(--text-white); margin-bottom: 8px; }
.step-card p { font-size: 0.88rem; color: var(--text-muted); }

/* ===== 视频弹窗 ===== */
.video-modal {
  display: none; position: fixed; inset: 0; z-index: 9999;
  background: rgba(0,0,0,0.88); align-items: center; justify-content: center;
}

.video-modal.show { display: flex; }

.modal-inner {
  background: var(--bg-card); border-radius: var(--radius);
  padding: 20px; max-width: 720px; width: 90%;
  position: relative;
}

.modal-close {
  position: absolute; top: 12px; right: 14px;
  background: none; border: none; color: var(--text-muted);
  font-size: 1.5rem; cursor: pointer; line-height: 1;
}

.modal-close:hover { color: #fff; }

.modal-video {
  width: 100%; aspect-ratio: 16/9;
  background: #000; border-radius: var(--radius-sm);
  overflow: hidden;
}

/* ===== 懒加载占位 ===== */
img[data-src] { background: var(--bg-card2); min-height: 80px; }

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

/* ===== 响应式 ===== */
@media (max-width: 768px) {
  #main-nav {
    display: none; position: fixed; top: 64px; left: 0; right: 0;
    background: var(--bg-dark); flex-direction: column;
    padding: 16px; border-bottom: 1px solid var(--border);
    z-index: 999;
  }

  #main-nav.open { display: flex; }
  .nav-toggle { display: flex; }

  .hero-content h1 { font-size: 2rem; }
  .video-grid { grid-template-columns: repeat(auto-fill, minmax(240px, 1fr)); }
  .stats-grid { grid-template-columns: repeat(2, 1fr); }
  .footer-bottom { flex-direction: column; text-align: center; }
  .media-sub-nav { gap: 8px; }
  .contact-grid { grid-template-columns: 1fr; }
}

@media (max-width: 480px) {
  .section { padding: 48px 16px; }
  .video-grid { grid-template-columns: 1fr; }
  .stats-grid { grid-template-columns: repeat(2, 1fr); }
  .hero-btns { flex-direction: column; align-items: center; }
  .ai-feature-grid { grid-template-columns: 1fr; }
  .expert-grid { grid-template-columns: 1fr; }
  .steps-grid { grid-template-columns: 1fr; }
  .review-grid { grid-template-columns: 1fr; }
}