/* =====================================================
   91 修车改装视频社区 - 原创样式系统
   品牌色：工业橙 #FF6B00 + 碳黑 #1A1A1A + 钢铁银 #C0C0C0
   域名：ggylsyea.cn
   ===================================================== */

/* ===== CSS变量 ===== */
:root {
  --primary: #FF6B00;
  --primary-dark: #CC5500;
  --primary-light: #FF8C33;
  --bg-dark: #0D0D0D;
  --bg-card: #1A1A1A;
  --bg-section: #141414;
  --bg-alt: #111111;
  --text-white: #F0F0F0;
  --text-gray: #999999;
  --text-light: #CCCCCC;
  --border: #2A2A2A;
  --border-orange: rgba(255,107,0,0.3);
  --silver: #C0C0C0;
  --carbon: #1E1E1E;
  --glow: 0 0 20px rgba(255,107,0,0.4);
  --shadow: 0 8px 32px rgba(0,0,0,0.6);
  --radius: 6px;
  --radius-lg: 12px;
  --transition: all 0.3s ease;
  --font-main: 'PingFang SC', 'Microsoft YaHei', 'Hiragino Sans GB', sans-serif;
}

/* ===== 重置与基础 ===== */
*, *::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(--bg-dark);
  color: var(--text-white);
  line-height: 1.7;
  overflow-x: hidden;
}
a { color: var(--primary); text-decoration: none; transition: var(--transition); }
a:hover { color: var(--primary-light); }
img { max-width: 100%; height: auto; display: block; }
ul, ol { list-style: none; }
button { cursor: pointer; border: none; outline: none; font-family: var(--font-main); }
input, textarea, select { font-family: var(--font-main); outline: none; }

/* ===== 隐藏干扰标签 ===== */
.nx-noise { display: none !important; visibility: hidden !important; }

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

/* ===== 顶部公告栏 ===== */
.top-bar {
  background: var(--primary);
  color: #fff;
  font-size: 0.78rem;
  padding: 6px 0;
  text-align: center;
  font-weight: 500;
  letter-spacing: 0.5px;
}
.top-bar a { color: #fff; font-weight: 700; }

/* ===== 头部导航 ===== */
.site-header {
  position: sticky;
  top: 0;
  z-index: 1000;
  background: rgba(13,13,13,0.97);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border-orange);
  box-shadow: 0 2px 20px rgba(0,0,0,0.5);
}
.header-inner {
  max-width: 1280px;
  margin: 0 auto;
  padding: 0 24px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 68px;
  gap: 20px;
}

/* Logo */
.site-logo {
  display: flex;
  align-items: center;
  gap: 12px;
  flex-shrink: 0;
}
.logo-icon {
  width: 44px;
  height: 44px;
  border-radius: var(--radius);
  overflow: hidden;
  border: 2px solid var(--primary);
  box-shadow: var(--glow);
}
.logo-icon img { width: 100%; height: 100%; object-fit: cover; }
.logo-text {
  font-size: 1.6rem;
  font-weight: 900;
  color: var(--text-white);
  letter-spacing: -1px;
  line-height: 1;
}
.logo-text span { color: var(--primary); }
.logo-sub {
  font-size: 0.65rem;
  color: var(--text-gray);
  font-weight: 400;
  letter-spacing: 1px;
  display: block;
  margin-top: 2px;
}

/* 主导航 */
.main-nav { display: flex; align-items: center; gap: 4px; }
.main-nav > li { position: relative; }
.main-nav > li > a {
  display: flex;
  align-items: center;
  gap: 4px;
  padding: 8px 14px;
  font-size: 0.88rem;
  font-weight: 600;
  color: var(--text-light);
  border-radius: var(--radius);
  transition: var(--transition);
  white-space: nowrap;
}
.main-nav > li > a:hover,
.main-nav > li > a.active {
  color: var(--primary);
  background: rgba(255,107,0,0.08);
}
.main-nav > li > a .nav-arrow {
  font-size: 0.6rem;
  transition: transform 0.3s;
}
.main-nav > li:hover > a .nav-arrow { transform: rotate(180deg); }

/* 下拉菜单 */
.dropdown {
  position: absolute;
  top: calc(100% + 8px);
  left: 0;
  min-width: 180px;
  background: var(--bg-card);
  border: 1px solid var(--border-orange);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  opacity: 0;
  visibility: hidden;
  transform: translateY(-8px);
  transition: var(--transition);
  z-index: 100;
}
.main-nav > li:hover .dropdown {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
}
.dropdown a {
  display: block;
  padding: 10px 16px;
  font-size: 0.84rem;
  color: var(--text-light);
  border-bottom: 1px solid var(--border);
  transition: var(--transition);
}
.dropdown a:last-child { border-bottom: none; }
.dropdown a:hover { color: var(--primary); background: rgba(255,107,0,0.06); padding-left: 22px; }

/* 搜索框 */
.header-search {
  display: flex;
  align-items: center;
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: 24px;
  padding: 6px 16px;
  gap: 8px;
  transition: var(--transition);
  min-width: 200px;
}
.header-search:focus-within {
  border-color: var(--primary);
  box-shadow: 0 0 0 3px rgba(255,107,0,0.15);
}
.header-search input {
  background: none;
  border: none;
  color: var(--text-white);
  font-size: 0.84rem;
  width: 100%;
}
.header-search input::placeholder { color: var(--text-gray); }
.search-btn {
  background: none;
  color: var(--text-gray);
  font-size: 0.9rem;
  padding: 0;
  transition: var(--transition);
}
.search-btn:hover { color: var(--primary); }

/* 汉堡菜单 */
.hamburger {
  display: none;
  flex-direction: column;
  gap: 5px;
  background: none;
  padding: 4px;
}
.hamburger span {
  display: block;
  width: 24px;
  height: 2px;
  background: var(--text-white);
  border-radius: 2px;
  transition: var(--transition);
}
.hamburger.active span:nth-child(1) { transform: rotate(45deg) translate(5px, 5px); }
.hamburger.active span:nth-child(2) { opacity: 0; }
.hamburger.active span:nth-child(3) { transform: rotate(-45deg) translate(5px, -5px); }

/* 搜索结果提示 */
.search-hint {
  display: none;
  position: absolute;
  top: 100%;
  right: 0;
  width: 300px;
  background: var(--bg-card);
  border: 1px solid var(--border-orange);
  border-radius: var(--radius);
  padding: 12px 16px;
  font-size: 0.82rem;
  color: var(--text-gray);
  box-shadow: var(--shadow);
  z-index: 200;
}
.search-wrapper { position: relative; }

/* ===== 面包屑 ===== */
.breadcrumb {
  background: var(--bg-section);
  border-bottom: 1px solid var(--border);
  padding: 10px 0;
}
.breadcrumb-inner {
  max-width: 1280px;
  margin: 0 auto;
  padding: 0 24px;
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 0.8rem;
  color: var(--text-gray);
}
.breadcrumb-inner a { color: var(--text-gray); }
.breadcrumb-inner a:hover { color: var(--primary); }
.breadcrumb-inner .sep { color: var(--border); }
.breadcrumb-inner .current { color: var(--primary); }

/* ===== Hero Banner ===== */
.hero-banner {
  position: relative;
  min-height: 88vh;
  display: flex;
  align-items: center;
  overflow: hidden;
}
.hero-bg {
  position: absolute;
  inset: 0;
  background-image: url('../images/banner.jpg');
  background-size: cover;
  background-position: center;
  transform: scale(1.05);
  transition: transform 8s ease;
}
.hero-bg::after {
  content: '';
  position: absolute;
  inset: 0;
  background: linear-gradient(
    135deg,
    rgba(13,13,13,0.92) 0%,
    rgba(13,13,13,0.7) 50%,
    rgba(255,107,0,0.15) 100%
  );
}
.hero-content {
  position: relative;
  z-index: 2;
  max-width: 1280px;
  margin: 0 auto;
  padding: 80px 24px;
  width: 100%;
}
.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  background: rgba(255,107,0,0.15);
  border: 1px solid var(--primary);
  border-radius: 24px;
  padding: 6px 16px;
  font-size: 0.78rem;
  color: var(--primary);
  font-weight: 600;
  margin-bottom: 24px;
  letter-spacing: 1px;
}
.hero-badge::before {
  content: '';
  width: 6px;
  height: 6px;
  background: var(--primary);
  border-radius: 50%;
  animation: pulse 1.5s infinite;
}
@keyframes pulse {
  0%, 100% { opacity: 1; transform: scale(1); }
  50% { opacity: 0.5; transform: scale(1.5); }
}
.hero-title {
  font-size: clamp(2.4rem, 5vw, 4.2rem);
  font-weight: 900;
  line-height: 1.1;
  margin-bottom: 20px;
  letter-spacing: -1px;
}
.hero-title .brand-name {
  color: var(--primary);
  text-shadow: 0 0 30px rgba(255,107,0,0.5);
}
.hero-title .line2 {
  display: block;
  font-size: 0.55em;
  color: var(--text-light);
  font-weight: 600;
  letter-spacing: 2px;
  margin-top: 8px;
}
.hero-desc {
  font-size: 1.05rem;
  color: var(--text-light);
  max-width: 600px;
  margin-bottom: 36px;
  line-height: 1.8;
}
.hero-stats {
  display: flex;
  gap: 40px;
  margin-bottom: 40px;
  flex-wrap: wrap;
}
.hero-stat-item { text-align: left; }
.hero-stat-num {
  font-size: 2rem;
  font-weight: 900;
  color: var(--primary);
  line-height: 1;
}
.hero-stat-label {
  font-size: 0.78rem;
  color: var(--text-gray);
  margin-top: 4px;
}
.hero-actions { display: flex; gap: 16px; flex-wrap: wrap; }

/* ===== 按钮系统 ===== */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 12px 28px;
  border-radius: var(--radius);
  font-size: 0.9rem;
  font-weight: 700;
  transition: var(--transition);
  letter-spacing: 0.5px;
}
.btn-primary {
  background: var(--primary);
  color: #fff;
  box-shadow: 0 4px 20px rgba(255,107,0,0.4);
}
.btn-primary:hover {
  background: var(--primary-dark);
  color: #fff;
  transform: translateY(-2px);
  box-shadow: 0 8px 30px rgba(255,107,0,0.5);
}
.btn-outline {
  background: transparent;
  color: var(--text-white);
  border: 2px solid var(--border);
}
.btn-outline:hover {
  border-color: var(--primary);
  color: var(--primary);
  transform: translateY(-2px);
}
.btn-sm { padding: 8px 18px; font-size: 0.82rem; }
.btn-lg { padding: 16px 36px; font-size: 1rem; }

/* ===== 站点简介条 ===== */
.site-intro-bar {
  background: linear-gradient(90deg, var(--bg-card) 0%, var(--carbon) 100%);
  border-top: 3px solid var(--primary);
  padding: 28px 0;
}
.site-intro-inner {
  max-width: 1280px;
  margin: 0 auto;
  padding: 0 24px;
  display: grid;
  grid-template-columns: 1fr auto;
  gap: 24px;
  align-items: center;
}
.site-intro-text h2 {
  font-size: 1.1rem;
  font-weight: 800;
  color: var(--text-white);
  margin-bottom: 8px;
}
.site-intro-text h2 span { color: var(--primary); }
.site-intro-text p {
  font-size: 0.85rem;
  color: var(--text-gray);
  line-height: 1.7;
}
.site-intro-tags { display: flex; gap: 8px; flex-wrap: wrap; margin-top: 12px; }
.intro-tag {
  background: rgba(255,107,0,0.1);
  border: 1px solid var(--border-orange);
  color: var(--primary);
  padding: 3px 10px;
  border-radius: 12px;
  font-size: 0.75rem;
  font-weight: 600;
}
.site-intro-meta {
  display: flex;
  flex-direction: column;
  gap: 8px;
  text-align: right;
}
.intro-meta-item {
  font-size: 0.78rem;
  color: var(--text-gray);
}
.intro-meta-item strong { color: var(--primary); }

/* ===== 通用区块 ===== */
.section {
  padding: 80px 0;
}
.section-alt { background: var(--bg-section); }
.section-dark { background: var(--bg-alt); }
.container {
  max-width: 1280px;
  margin: 0 auto;
  padding: 0 24px;
}
.section-header {
  margin-bottom: 48px;
}
.section-label {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-size: 0.75rem;
  font-weight: 700;
  color: var(--primary);
  letter-spacing: 2px;
  text-transform: uppercase;
  margin-bottom: 12px;
}
.section-label::before {
  content: '';
  width: 24px;
  height: 2px;
  background: var(--primary);
}
.section-title {
  font-size: clamp(1.6rem, 3vw, 2.4rem);
  font-weight: 900;
  color: var(--text-white);
  line-height: 1.2;
  margin-bottom: 12px;
}
.section-title span { color: var(--primary); }
.section-desc {
  font-size: 0.95rem;
  color: var(--text-gray);
  max-width: 600px;
  line-height: 1.8;
}
.section-header-flex {
  display: flex;
  align-items: flex-end;
  justify-content: space-between;
  gap: 20px;
  margin-bottom: 40px;
  flex-wrap: wrap;
}

/* ===== 视频卡片系统 ===== */
.video-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 24px;
}
.video-grid-4 { grid-template-columns: repeat(4, 1fr); }
.video-grid-3 { grid-template-columns: repeat(3, 1fr); }

.video-card {
  background: var(--bg-card);
  border-radius: var(--radius-lg);
  overflow: hidden;
  border: 1px solid var(--border);
  transition: var(--transition);
  cursor: pointer;
}
.video-card:hover {
  border-color: var(--primary);
  transform: translateY(-4px);
  box-shadow: 0 12px 40px rgba(255,107,0,0.2);
}
.video-thumb {
  position: relative;
  aspect-ratio: 16/9;
  overflow: hidden;
  background: #111;
}
.video-thumb img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform 0.5s ease;
}
.video-card:hover .video-thumb img { transform: scale(1.08); }
.video-play-btn {
  position: absolute;
  inset: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  background: rgba(0,0,0,0.3);
  opacity: 0;
  transition: var(--transition);
}
.video-card:hover .video-play-btn { opacity: 1; }
.play-icon {
  width: 56px;
  height: 56px;
  background: var(--primary);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  box-shadow: 0 0 30px rgba(255,107,0,0.6);
  transform: scale(0.8);
  transition: var(--transition);
}
.video-card:hover .play-icon { transform: scale(1); }
.play-icon::after {
  content: '';
  width: 0;
  height: 0;
  border-style: solid;
  border-width: 10px 0 10px 18px;
  border-color: transparent transparent transparent #fff;
  margin-left: 4px;
}
.video-duration {
  position: absolute;
  bottom: 8px;
  right: 8px;
  background: rgba(0,0,0,0.8);
  color: #fff;
  font-size: 0.72rem;
  padding: 2px 7px;
  border-radius: 3px;
  font-weight: 600;
}
.video-badge {
  position: absolute;
  top: 8px;
  left: 8px;
  background: var(--primary);
  color: #fff;
  font-size: 0.68rem;
  padding: 2px 8px;
  border-radius: 3px;
  font-weight: 700;
  letter-spacing: 0.5px;
}
.video-badge.hot { background: #e53e3e; }
.video-badge.new { background: #38a169; }
.video-badge.award { background: #d69e2e; }

.video-info { padding: 16px; }
.video-meta {
  display: flex;
  align-items: center;
  gap: 8px;
  margin-bottom: 8px;
}
.video-cat {
  font-size: 0.7rem;
  color: var(--primary);
  font-weight: 700;
  background: rgba(255,107,0,0.1);
  padding: 2px 8px;
  border-radius: 10px;
}
.video-date { font-size: 0.72rem; color: var(--text-gray); margin-left: auto; }
.video-title {
  font-size: 0.92rem;
  font-weight: 700;
  color: var(--text-white);
  line-height: 1.4;
  margin-bottom: 10px;
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
}
.video-stats {
  display: flex;
  gap: 14px;
  font-size: 0.75rem;
  color: var(--text-gray);
}
.video-stats span { display: flex; align-items: center; gap: 4px; }

/* TikTok竖屏卡片 */
.tiktok-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(180px, 1fr));
  gap: 16px;
}
.tiktok-card {
  background: var(--bg-card);
  border-radius: var(--radius-lg);
  overflow: hidden;
  border: 1px solid var(--border);
  transition: var(--transition);
  cursor: pointer;
}
.tiktok-card:hover {
  border-color: var(--primary);
  transform: translateY(-4px);
  box-shadow: 0 12px 40px rgba(255,107,0,0.2);
}
.tiktok-thumb {
  position: relative;
  aspect-ratio: 9/16;
  overflow: hidden;
  background: #111;
}
.tiktok-thumb img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform 0.5s ease;
}
.tiktok-card:hover .tiktok-thumb img { transform: scale(1.08); }
.tiktok-play {
  position: absolute;
  inset: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  background: rgba(0,0,0,0.25);
  opacity: 0;
  transition: var(--transition);
}
.tiktok-card:hover .tiktok-play { opacity: 1; }
.tiktok-play .play-icon { width: 44px; height: 44px; }
.tiktok-info { padding: 12px; }
.tiktok-title {
  font-size: 0.82rem;
  font-weight: 600;
  color: var(--text-white);
  line-height: 1.4;
  margin-bottom: 6px;
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
}
.tiktok-views { font-size: 0.72rem; color: var(--text-gray); }

/* ===== 视频弹窗 ===== */
.video-modal {
  display: none;
  position: fixed;
  inset: 0;
  z-index: 9999;
  background: rgba(0,0,0,0.92);
  align-items: center;
  justify-content: center;
  padding: 20px;
}
.video-modal.active { display: flex; }
.modal-content {
  background: var(--bg-card);
  border-radius: var(--radius-lg);
  border: 1px solid var(--border-orange);
  max-width: 860px;
  width: 100%;
  overflow: hidden;
  box-shadow: 0 20px 80px rgba(0,0,0,0.8);
}
.modal-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 16px 20px;
  border-bottom: 1px solid var(--border);
}
.modal-title { font-size: 0.95rem; font-weight: 700; color: var(--text-white); }
.modal-close {
  width: 32px;
  height: 32px;
  background: var(--bg-dark);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--text-gray);
  font-size: 1.2rem;
  transition: var(--transition);
}
.modal-close:hover { background: var(--primary); color: #fff; }
.modal-video {
  aspect-ratio: 16/9;
  background: #000;
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--text-gray);
  font-size: 0.9rem;
}
.modal-video-placeholder {
  text-align: center;
  padding: 40px;
}
.modal-video-placeholder .big-play {
  width: 80px;
  height: 80px;
  background: var(--primary);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  margin: 0 auto 16px;
  box-shadow: var(--glow);
}
.modal-video-placeholder .big-play::after {
  content: '';
  width: 0;
  height: 0;
  border-style: solid;
  border-width: 14px 0 14px 24px;
  border-color: transparent transparent transparent #fff;
  margin-left: 6px;
}

/* ===== 功能模块卡片 ===== */
.feature-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}
.feature-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 28px;
  transition: var(--transition);
  position: relative;
  overflow: hidden;
}
.feature-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 3px;
  background: var(--primary);
  transform: scaleX(0);
  transition: transform 0.3s ease;
}
.feature-card:hover::before { transform: scaleX(1); }
.feature-card:hover {
  border-color: var(--border-orange);
  transform: translateY(-4px);
  box-shadow: var(--shadow);
}
.feature-icon {
  width: 52px;
  height: 52px;
  background: rgba(255,107,0,0.1);
  border: 1px solid var(--border-orange);
  border-radius: var(--radius);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.4rem;
  margin-bottom: 16px;
}
.feature-title {
  font-size: 1rem;
  font-weight: 800;
  color: var(--text-white);
  margin-bottom: 8px;
}
.feature-title span { color: var(--primary); }
.feature-desc {
  font-size: 0.84rem;
  color: var(--text-gray);
  line-height: 1.7;
}
.feature-link {
  display: inline-flex;
  align-items: center;
  gap: 4px;
  font-size: 0.8rem;
  color: var(--primary);
  font-weight: 600;
  margin-top: 14px;
}
.feature-link:hover { gap: 8px; }

/* ===== AI赋能模块 ===== */
.ai-section {
  background: linear-gradient(135deg, var(--bg-alt) 0%, #0A0A1A 100%);
  position: relative;
  overflow: hidden;
}
.ai-section::before {
  content: '';
  position: absolute;
  top: -50%;
  right: -20%;
  width: 600px;
  height: 600px;
  background: radial-gradient(circle, rgba(255,107,0,0.08) 0%, transparent 70%);
  pointer-events: none;
}
.ai-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 60px;
  align-items: center;
}
.ai-visual {
  position: relative;
  border-radius: var(--radius-lg);
  overflow: hidden;
  border: 1px solid var(--border-orange);
  box-shadow: var(--glow);
}
.ai-visual img { width: 100%; display: block; }
.ai-overlay {
  position: absolute;
  bottom: 0;
  left: 0;
  right: 0;
  background: linear-gradient(to top, rgba(0,0,0,0.9) 0%, transparent 100%);
  padding: 24px;
}
.ai-overlay-text {
  font-size: 0.82rem;
  color: var(--primary);
  font-weight: 700;
  letter-spacing: 1px;
}
.ai-features { display: flex; flex-direction: column; gap: 20px; }
.ai-feature-item {
  display: flex;
  gap: 16px;
  align-items: flex-start;
  padding: 20px;
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  transition: var(--transition);
}
.ai-feature-item:hover {
  border-color: var(--border-orange);
  box-shadow: 0 4px 20px rgba(255,107,0,0.1);
}
.ai-icon {
  width: 44px;
  height: 44px;
  background: rgba(255,107,0,0.1);
  border-radius: var(--radius);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.2rem;
  flex-shrink: 0;
}
.ai-feature-title {
  font-size: 0.92rem;
  font-weight: 700;
  color: var(--text-white);
  margin-bottom: 4px;
}
.ai-feature-desc {
  font-size: 0.82rem;
  color: var(--text-gray);
  line-height: 1.6;
}

/* ===== 专家团队 ===== */
.expert-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}
.expert-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  overflow: hidden;
  transition: var(--transition);
}
.expert-card:hover {
  border-color: var(--border-orange);
  transform: translateY(-4px);
  box-shadow: var(--shadow);
}
.expert-photo {
  aspect-ratio: 3/4;
  overflow: hidden;
  background: var(--bg-dark);
}
.expert-photo img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform 0.5s ease;
}
.expert-card:hover .expert-photo img { transform: scale(1.05); }
.expert-info { padding: 20px; }
.expert-role {
  font-size: 0.72rem;
  color: var(--primary);
  font-weight: 700;
  letter-spacing: 1px;
  text-transform: uppercase;
  margin-bottom: 6px;
}
.expert-name {
  font-size: 1.1rem;
  font-weight: 800;
  color: var(--text-white);
  margin-bottom: 8px;
}
.expert-name span { color: var(--primary); }
.expert-bio {
  font-size: 0.82rem;
  color: var(--text-gray);
  line-height: 1.6;
  margin-bottom: 14px;
}
.expert-tags { display: flex; flex-wrap: wrap; gap: 6px; margin-bottom: 14px; }
.expert-tag {
  background: rgba(255,107,0,0.08);
  border: 1px solid var(--border-orange);
  color: var(--primary);
  font-size: 0.68rem;
  padding: 2px 8px;
  border-radius: 10px;
  font-weight: 600;
}
.expert-actions { display: flex; gap: 8px; }
.expert-actions .btn { flex: 1; justify-content: center; }

/* ===== 社区功能 ===== */
.community-layout {
  display: grid;
  grid-template-columns: 2fr 1fr;
  gap: 40px;
}
.community-topics { display: flex; flex-direction: column; gap: 16px; }
.topic-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 20px;
  display: flex;
  gap: 16px;
  align-items: flex-start;
  transition: var(--transition);
}
.topic-card:hover {
  border-color: var(--border-orange);
  background: rgba(255,107,0,0.04);
}
.topic-icon {
  width: 48px;
  height: 48px;
  background: rgba(255,107,0,0.1);
  border-radius: var(--radius);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.3rem;
  flex-shrink: 0;
}
.topic-title {
  font-size: 0.95rem;
  font-weight: 700;
  color: var(--text-white);
  margin-bottom: 4px;
}
.topic-meta {
  font-size: 0.78rem;
  color: var(--text-gray);
  display: flex;
  gap: 12px;
}
.community-sidebar { display: flex; flex-direction: column; gap: 20px; }
.sidebar-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 20px;
}
.sidebar-title {
  font-size: 0.9rem;
  font-weight: 800;
  color: var(--text-white);
  margin-bottom: 16px;
  padding-bottom: 10px;
  border-bottom: 1px solid var(--border);
}
.sidebar-title span { color: var(--primary); }

/* ===== 合作品牌 ===== */
.partners-grid {
  display: grid;
  grid-template-columns: repeat(6, 1fr);
  gap: 16px;
}
.partner-item {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 16px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 0.82rem;
  font-weight: 700;
  color: var(--text-gray);
  transition: var(--transition);
  text-align: center;
  min-height: 60px;
}
.partner-item:hover {
  border-color: var(--primary);
  color: var(--primary);
  background: rgba(255,107,0,0.05);
}

/* ===== 加入步骤 ===== */
.steps-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 24px;
  position: relative;
}
.steps-grid::before {
  content: '';
  position: absolute;
  top: 28px;
  left: 12%;
  right: 12%;
  height: 2px;
  background: linear-gradient(90deg, var(--primary) 0%, var(--border) 100%);
  z-index: 0;
}
.step-item {
  position: relative;
  z-index: 1;
  text-align: center;
  padding: 24px 16px;
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  transition: var(--transition);
}
.step-item:hover {
  border-color: var(--border-orange);
  transform: translateY(-4px);
}
.step-num {
  width: 52px;
  height: 52px;
  background: var(--primary);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.2rem;
  font-weight: 900;
  color: #fff;
  margin: 0 auto 16px;
  box-shadow: 0 4px 16px rgba(255,107,0,0.4);
}
.step-title {
  font-size: 0.9rem;
  font-weight: 800;
  color: var(--text-white);
  margin-bottom: 8px;
}
.step-desc {
  font-size: 0.8rem;
  color: var(--text-gray);
  line-height: 1.6;
}

/* ===== 用户评价 ===== */
.reviews-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}
.review-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 24px;
  transition: var(--transition);
  position: relative;
}
.review-card::before {
  content: '"';
  position: absolute;
  top: 16px;
  right: 20px;
  font-size: 4rem;
  color: rgba(255,107,0,0.1);
  font-family: Georgia, serif;
  line-height: 1;
}
.review-card:hover {
  border-color: var(--border-orange);
  box-shadow: 0 8px 30px rgba(255,107,0,0.1);
}
.review-stars {
  display: flex;
  gap: 2px;
  margin-bottom: 12px;
  color: var(--primary);
  font-size: 0.9rem;
}
.review-text {
  font-size: 0.88rem;
  color: var(--text-light);
  line-height: 1.7;
  margin-bottom: 16px;
}
.review-author {
  display: flex;
  align-items: center;
  gap: 10px;
}
.review-avatar {
  width: 38px;
  height: 38px;
  border-radius: 50%;
  background: var(--primary);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 0.9rem;
  font-weight: 700;
  color: #fff;
  flex-shrink: 0;
}
.review-name {
  font-size: 0.85rem;
  font-weight: 700;
  color: var(--text-white);
}
.review-role { font-size: 0.75rem; color: var(--text-gray); }

/* ===== FAQ ===== */
.faq-list { max-width: 800px; margin: 0 auto; }
.faq-item {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  margin-bottom: 12px;
  overflow: hidden;
  transition: var(--transition);
}
.faq-item.active { border-color: var(--border-orange); }
.faq-question {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 18px 20px;
  cursor: pointer;
  font-size: 0.92rem;
  font-weight: 700;
  color: var(--text-white);
  transition: var(--transition);
  gap: 12px;
}
.faq-question:hover { color: var(--primary); }
.faq-item.active .faq-question { color: var(--primary); }
.faq-icon {
  width: 24px;
  height: 24px;
  background: rgba(255,107,0,0.1);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 0.8rem;
  color: var(--primary);
  flex-shrink: 0;
  transition: transform 0.3s ease;
}
.faq-item.active .faq-icon { transform: rotate(45deg); }
.faq-answer {
  display: none;
  padding: 0 20px 18px;
  font-size: 0.86rem;
  color: var(--text-gray);
  line-height: 1.8;
}
.faq-item.active .faq-answer { display: block; }

/* ===== 联系我们 ===== */
.contact-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 40px;
}
.contact-info { display: flex; flex-direction: column; gap: 16px; }
.contact-item {
  display: flex;
  gap: 14px;
  align-items: flex-start;
  padding: 16px;
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  transition: var(--transition);
}
.contact-item:hover { border-color: var(--border-orange); }
.contact-icon {
  width: 40px;
  height: 40px;
  background: rgba(255,107,0,0.1);
  border-radius: var(--radius);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.1rem;
  flex-shrink: 0;
}
.contact-label { font-size: 0.75rem; color: var(--text-gray); margin-bottom: 2px; }
.contact-value { font-size: 0.9rem; font-weight: 700; color: var(--text-white); }
.contact-form { display: flex; flex-direction: column; gap: 14px; }
.form-row { display: grid; grid-template-columns: 1fr 1fr; gap: 14px; }
.form-group { display: flex; flex-direction: column; gap: 6px; }
.form-label { font-size: 0.8rem; color: var(--text-gray); font-weight: 600; }
.form-input, .form-textarea, .form-select {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 10px 14px;
  color: var(--text-white);
  font-size: 0.88rem;
  transition: var(--transition);
}
.form-input:focus, .form-textarea:focus, .form-select:focus {
  border-color: var(--primary);
  box-shadow: 0 0 0 3px rgba(255,107,0,0.12);
}
.form-textarea { min-height: 120px; resize: vertical; }

/* ===== 社交分享 ===== */
.share-bar {
  display: flex;
  align-items: center;
  gap: 12px;
  flex-wrap: wrap;
}
.share-label { font-size: 0.82rem; color: var(--text-gray); font-weight: 600; }
.share-btn {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 7px 14px;
  border-radius: var(--radius);
  font-size: 0.78rem;
  font-weight: 700;
  transition: var(--transition);
  border: 1px solid var(--border);
  color: var(--text-light);
  background: var(--bg-card);
}
.share-btn:hover { transform: translateY(-2px); }
.share-btn.wechat:hover { border-color: #07c160; color: #07c160; }
.share-btn.weibo:hover { border-color: #e6162d; color: #e6162d; }
.share-btn.douyin:hover { border-color: #fe2c55; color: #fe2c55; }
.share-btn.bilibili:hover { border-color: #00a1d6; color: #00a1d6; }
.share-btn.qq:hover { border-color: #12b7f5; color: #12b7f5; }

/* ===== 数据统计条 ===== */
.stats-bar {
  background: var(--primary);
  padding: 24px 0;
}
.stats-inner {
  max-width: 1280px;
  margin: 0 auto;
  padding: 0 24px;
  display: grid;
  grid-template-columns: repeat(5, 1fr);
  gap: 20px;
}
.stat-item { text-align: center; }
.stat-num {
  font-size: 1.8rem;
  font-weight: 900;
  color: #fff;
  line-height: 1;
}
.stat-label {
  font-size: 0.75rem;
  color: rgba(255,255,255,0.8);
  margin-top: 4px;
}

/* ===== 页脚 ===== */
.site-footer {
  background: #080808;
  border-top: 1px solid var(--border);
  padding: 60px 0 0;
}
.footer-grid {
  max-width: 1280px;
  margin: 0 auto;
  padding: 0 24px;
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1fr;
  gap: 40px;
  margin-bottom: 40px;
}
.footer-brand .logo-text { font-size: 1.8rem; margin-bottom: 12px; display: block; }
.footer-desc {
  font-size: 0.84rem;
  color: var(--text-gray);
  line-height: 1.8;
  margin-bottom: 20px;
}
.footer-qr-row { display: flex; gap: 20px; }
.footer-qr-item { text-align: center; }
.footer-qr-box {
  width: 80px;
  height: 80px;
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 0.65rem;
  color: var(--text-gray);
  margin-bottom: 6px;
  text-align: center;
  padding: 6px;
  line-height: 1.4;
}
.footer-qr-label { font-size: 0.7rem; color: var(--text-gray); }
.footer-col-title {
  font-size: 0.88rem;
  font-weight: 800;
  color: var(--text-white);
  margin-bottom: 16px;
  padding-bottom: 10px;
  border-bottom: 1px solid var(--border);
}
.footer-col-title span { color: var(--primary); }
.footer-links { display: flex; flex-direction: column; gap: 8px; }
.footer-links a {
  font-size: 0.82rem;
  color: var(--text-gray);
  transition: var(--transition);
  display: flex;
  align-items: center;
  gap: 6px;
}
.footer-links a:hover { color: var(--primary); padding-left: 4px; }
.footer-links a::before {
  content: '›';
  color: var(--primary);
  font-size: 1rem;
}
.footer-bottom {
  border-top: 1px solid var(--border);
  padding: 20px 24px;
  max-width: 1280px;
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 12px;
}
.footer-copyright {
  font-size: 0.78rem;
  color: var(--text-gray);
}
.footer-copyright a { color: var(--text-gray); }
.footer-copyright a:hover { color: var(--primary); }
.footer-update {
  font-size: 0.75rem;
  color: var(--text-gray);
}
.footer-update strong { color: var(--primary); }
.footer-legal { display: flex; gap: 16px; }
.footer-legal a { font-size: 0.75rem; color: var(--text-gray); }
.footer-legal a:hover { color: var(--primary); }

/* ===== 内页Hero ===== */
.page-hero {
  background: linear-gradient(135deg, var(--bg-section) 0%, var(--bg-alt) 100%);
  border-bottom: 1px solid var(--border);
  padding: 60px 0;
  position: relative;
  overflow: hidden;
}
.page-hero::before {
  content: '';
  position: absolute;
  top: -50%;
  right: -10%;
  width: 400px;
  height: 400px;
  background: radial-gradient(circle, rgba(255,107,0,0.06) 0%, transparent 70%);
}
.page-hero-inner {
  max-width: 1280px;
  margin: 0 auto;
  padding: 0 24px;
  position: relative;
  z-index: 1;
}
.page-hero-title {
  font-size: clamp(1.8rem, 3vw, 2.8rem);
  font-weight: 900;
  color: var(--text-white);
  margin-bottom: 12px;
}
.page-hero-title span { color: var(--primary); }
.page-hero-desc {
  font-size: 0.95rem;
  color: var(--text-gray);
  max-width: 600px;
  line-height: 1.8;
}

/* ===== 标签筛选 ===== */
.filter-tabs {
  display: flex;
  gap: 8px;
  flex-wrap: wrap;
  margin-bottom: 32px;
}
.filter-tab {
  padding: 7px 18px;
  border-radius: 24px;
  font-size: 0.82rem;
  font-weight: 600;
  border: 1px solid var(--border);
  color: var(--text-gray);
  background: var(--bg-card);
  transition: var(--transition);
  cursor: pointer;
}
.filter-tab:hover, .filter-tab.active {
  border-color: var(--primary);
  color: var(--primary);
  background: rgba(255,107,0,0.08);
}

/* ===== 分页 ===== */
.pagination {
  display: flex;
  justify-content: center;
  gap: 8px;
  margin-top: 48px;
}
.page-btn {
  width: 40px;
  height: 40px;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: var(--radius);
  font-size: 0.88rem;
  font-weight: 600;
  border: 1px solid var(--border);
  color: var(--text-gray);
  background: var(--bg-card);
  transition: var(--transition);
  cursor: pointer;
}
.page-btn:hover, .page-btn.active {
  border-color: var(--primary);
  color: var(--primary);
  background: rgba(255,107,0,0.08);
}

/* ===== 时间轴 ===== */
.timeline { position: relative; padding-left: 32px; }
.timeline::before {
  content: '';
  position: absolute;
  left: 0;
  top: 0;
  bottom: 0;
  width: 2px;
  background: linear-gradient(to bottom, var(--primary) 0%, var(--border) 100%);
}
.timeline-item {
  position: relative;
  margin-bottom: 32px;
  padding-left: 24px;
}
.timeline-item::before {
  content: '';
  position: absolute;
  left: -38px;
  top: 4px;
  width: 12px;
  height: 12px;
  background: var(--primary);
  border-radius: 50%;
  border: 2px solid var(--bg-dark);
  box-shadow: 0 0 0 3px rgba(255,107,0,0.3);
}
.timeline-year {
  font-size: 0.75rem;
  color: var(--primary);
  font-weight: 700;
  letter-spacing: 1px;
  margin-bottom: 4px;
}
.timeline-title {
  font-size: 0.95rem;
  font-weight: 800;
  color: var(--text-white);
  margin-bottom: 6px;
}
.timeline-desc {
  font-size: 0.84rem;
  color: var(--text-gray);
  line-height: 1.7;
}

/* ===== 关键词标签云 ===== */
.keyword-cloud {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin: 20px 0;
}
.kw-tag {
  background: rgba(255,107,0,0.06);
  border: 1px solid rgba(255,107,0,0.2);
  color: var(--text-gray);
  padding: 4px 12px;
  border-radius: 14px;
  font-size: 0.78rem;
  transition: var(--transition);
  cursor: default;
}
.kw-tag:hover {
  background: rgba(255,107,0,0.12);
  color: var(--primary);
  border-color: var(--primary);
}

/* ===== 加载动画 ===== */
.skeleton {
  background: linear-gradient(90deg, var(--bg-card) 25%, var(--border) 50%, var(--bg-card) 75%);
  background-size: 200% 100%;
  animation: skeleton-loading 1.5s infinite;
  border-radius: var(--radius);
}
@keyframes skeleton-loading {
  0% { background-position: 200% 0; }
  100% { background-position: -200% 0; }
}

/* ===== 移动端适配 ===== */
@media (max-width: 1024px) {
  .video-grid-4 { grid-template-columns: repeat(2, 1fr); }
  .feature-grid { grid-template-columns: repeat(2, 1fr); }
  .expert-grid { grid-template-columns: repeat(2, 1fr); }
  .ai-grid { grid-template-columns: 1fr; }
  .ai-visual { max-width: 600px; }
  .steps-grid { grid-template-columns: repeat(2, 1fr); }
  .steps-grid::before { display: none; }
  .partners-grid { grid-template-columns: repeat(3, 1fr); }
  .stats-inner { grid-template-columns: repeat(3, 1fr); }
  .footer-grid { grid-template-columns: 1fr 1fr; }
}

@media (max-width: 768px) {
  .main-nav { display: none; }
  .hamburger { display: flex; }
  .header-search { display: none; }
  .hero-banner { min-height: 70vh; }
  .hero-stats { gap: 24px; }
  .hero-stat-num { font-size: 1.5rem; }
  .site-intro-inner { grid-template-columns: 1fr; }
  .site-intro-meta { text-align: left; }
  .video-grid-4, .video-grid-3 { grid-template-columns: repeat(2, 1fr); }
  .feature-grid { grid-template-columns: 1fr; }
  .expert-grid { grid-template-columns: 1fr; }
  .reviews-grid { grid-template-columns: 1fr; }
  .contact-grid { grid-template-columns: 1fr; }
  .community-layout { grid-template-columns: 1fr; }
  .steps-grid { grid-template-columns: 1fr; }
  .partners-grid { grid-template-columns: repeat(2, 1fr); }
  .stats-inner { grid-template-columns: repeat(2, 1fr); }
  .footer-grid { grid-template-columns: 1fr; }
  .footer-bottom { flex-direction: column; text-align: center; }
  .tiktok-grid { grid-template-columns: repeat(2, 1fr); }
  .form-row { grid-template-columns: 1fr; }
  .section { padding: 50px 0; }

  /* 移动端导航展开 */
  .mobile-nav {
    display: none;
    position: fixed;
    top: 68px;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(13,13,13,0.98);
    z-index: 999;
    overflow-y: auto;
    padding: 20px;
  }
  .mobile-nav.active { display: block; }
  .mobile-nav a {
    display: block;
    padding: 14px 0;
    font-size: 1rem;
    font-weight: 600;
    color: var(--text-light);
    border-bottom: 1px solid var(--border);
  }
  .mobile-nav a:hover { color: var(--primary); }
  .mobile-search {
    display: flex;
    margin-bottom: 20px;
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: 10px 14px;
    gap: 8px;
  }
  .mobile-search input {
    background: none;
    border: none;
    color: var(--text-white);
    font-size: 0.9rem;
    flex: 1;
  }
}

@media (max-width: 480px) {
  .video-grid, .video-grid-4, .video-grid-3 { grid-template-columns: 1fr; }
  .tiktok-grid { grid-template-columns: repeat(2, 1fr); }
  .hero-title { font-size: 2rem; }
  .hero-actions { flex-direction: column; }
  .hero-actions .btn { width: 100%; justify-content: center; }
}

/* ===== 打印样式 ===== */
@media print {
  .site-header, .site-footer, .video-modal { display: none; }
  body { background: #fff; color: #000; }
}

/* ===== 面包屑导航 ===== */
.breadcrumb-bar { background:#111; border-bottom:1px solid #222; padding:10px 0; }
.breadcrumb { list-style:none; display:flex; align-items:center; gap:6px; margin:0; padding:0; font-size:.82rem; }
.breadcrumb li { color:#666; }
.breadcrumb a { color:#999; text-decoration:none; }
.breadcrumb a:hover { color:var(--primary); }
.breadcrumb .sep { color:#444; }

/* ===== 联系表单 ===== */
.form-group { margin-bottom:16px; }
.form-group label { display:block; color:#ccc; font-size:.85rem; margin-bottom:6px; }
.form-input { width:100%; background:#1a1a1a; border:1px solid #333; color:#eee; padding:10px 14px; border-radius:var(--radius); font-size:.9rem; outline:none; transition:var(--transition); box-sizing:border-box; }
.form-input:focus { border-color:var(--primary); box-shadow:0 0 0 2px rgba(255,107,0,.15); }
.form-input option { background:#1a1a1a; }

/* ===== 关于页面时间轴 ===== */
.timeline { position:relative; padding-left:32px; }
.timeline::before { content:''; position:absolute; left:0; top:0; bottom:0; width:2px; background:linear-gradient(to bottom, var(--primary), transparent); }
.timeline-item { position:relative; margin-bottom:32px; }
.timeline-item::before { content:''; position:absolute; left:-38px; top:6px; width:12px; height:12px; background:var(--primary); border-radius:50%; box-shadow:var(--glow); }
.timeline-year { color:var(--primary); font-size:.85rem; font-weight:700; margin-bottom:6px; }
.timeline-content h3 { color:#eee; font-size:1rem; margin:0 0 6px; }
.timeline-content p { color:#999; font-size:.85rem; line-height:1.7; margin:0; }

/* ===== 合作品牌 ===== */
.partners-grid { display:grid; grid-template-columns:repeat(6,1fr); gap:12px; }
.partner-item { background:#1a1a1a; border:1px solid #2a2a2a; padding:16px 12px; text-align:center; border-radius:var(--radius); color:#999; font-size:.82rem; transition:var(--transition); }
.partner-item:hover { border-color:var(--primary); color:var(--primary); }
@media(max-width:768px) { .partners-grid { grid-template-columns:repeat(3,1fr); } }
@media(max-width:480px) { .partners-grid { grid-template-columns:repeat(2,1fr); } }

/* ===== 加入步骤 ===== */
.steps-grid { display:grid; grid-template-columns:repeat(4,1fr); gap:24px; margin-top:32px; }
.step-item { text-align:center; padding:28px 20px; background:#1a1a1a; border:1px solid #2a2a2a; border-radius:var(--radius-lg); transition:var(--transition); }
.step-item:hover { border-color:var(--primary); transform:translateY(-4px); }
.step-num { width:48px; height:48px; background:var(--primary); color:#fff; font-size:1.4rem; font-weight:900; border-radius:50%; display:flex; align-items:center; justify-content:center; margin:0 auto 16px; }
.step-title { color:#eee; font-size:.95rem; font-weight:600; margin-bottom:10px; }
.step-desc { color:#999; font-size:.82rem; line-height:1.7; }
@media(max-width:768px) { .steps-grid { grid-template-columns:repeat(2,1fr); } }
@media(max-width:480px) { .steps-grid { grid-template-columns:1fr; } }

/* ===== 社交分享 ===== */
.share-bar { display:flex; align-items:center; gap:12px; flex-wrap:wrap; }
.share-label { color:#999; font-size:.85rem; }
.share-btn { padding:8px 18px; border-radius:20px; font-size:.82rem; text-decoration:none; border:1px solid #333; color:#ccc; transition:var(--transition); }
.share-btn:hover { border-color:var(--primary); color:var(--primary); }

/* ===== 站点简介条 ===== */
.site-intro-bar { background:#111; border-top:2px solid var(--primary); border-bottom:1px solid #222; padding:32px 0; }
.site-intro-inner { max-width:1200px; margin:0 auto; padding:0 24px; display:grid; grid-template-columns:1fr auto; gap:32px; align-items:start; }
.site-intro-text h2 { color:#eee; font-size:1.1rem; margin:0 0 12px; }
.site-intro-text h2 span { color:var(--primary); }
.site-intro-text p { color:#999; font-size:.88rem; line-height:1.8; margin:0 0 16px; }
.site-intro-tags { display:flex; flex-wrap:wrap; gap:8px; }
.intro-tag { background:#1a1a1a; border:1px solid #333; color:#999; padding:4px 12px; border-radius:12px; font-size:.78rem; }
.site-intro-meta { display:flex; flex-direction:column; gap:8px; min-width:180px; }
.intro-meta-item { color:#666; font-size:.82rem; }
.intro-meta-item strong { color:var(--primary); }
@media(max-width:768px) { .site-intro-inner { grid-template-columns:1fr; } }

/* ===== 社区布局 ===== */
.community-layout { display:grid; grid-template-columns:1fr 320px; gap:32px; }
.community-sidebar { display:flex; flex-direction:column; gap:20px; }
.sidebar-card { background:#1a1a1a; border:1px solid #2a2a2a; border-radius:var(--radius-lg); padding:20px; }
.sidebar-title { color:#eee; font-size:.9rem; font-weight:600; margin-bottom:14px; }
.sidebar-title span { color:var(--primary); }
.community-topics { display:flex; flex-direction:column; gap:12px; }
.topic-card { background:#1a1a1a; border:1px solid #2a2a2a; border-radius:var(--radius); padding:16px; display:flex; gap:14px; align-items:flex-start; transition:var(--transition); }
.topic-card:hover { border-color:var(--primary); }
.topic-icon { font-size:1.4rem; flex-shrink:0; }
.topic-title { color:#eee; font-size:.9rem; font-weight:600; margin-bottom:6px; }
.topic-meta { display:flex; gap:12px; font-size:.78rem; color:#666; flex-wrap:wrap; }
@media(max-width:1024px) { .community-layout { grid-template-columns:1fr; } }

/* ===== TikTok风格视频 ===== */
.tiktok-grid { display:grid; grid-template-columns:repeat(6,1fr); gap:12px; }
.tiktok-card { background:#1a1a1a; border:1px solid #2a2a2a; border-radius:var(--radius); overflow:hidden; cursor:pointer; transition:var(--transition); }
.tiktok-card:hover { border-color:var(--primary); transform:translateY(-4px); }
.tiktok-thumb { position:relative; aspect-ratio:9/16; overflow:hidden; }
.tiktok-thumb img { width:100%; height:100%; object-fit:cover; transition:transform .4s; }
.tiktok-card:hover .tiktok-thumb img { transform:scale(1.05); }
.tiktok-play { position:absolute; inset:0; display:flex; align-items:center; justify-content:center; background:rgba(0,0,0,.3); opacity:0; transition:var(--transition); }
.tiktok-card:hover .tiktok-play { opacity:1; }
.tiktok-info { padding:10px; }
.tiktok-title { color:#eee; font-size:.78rem; line-height:1.5; margin-bottom:4px; display:-webkit-box; -webkit-line-clamp:2; -webkit-box-orient:vertical; overflow:hidden; }
.tiktok-views { color:#666; font-size:.72rem; }
@media(max-width:1024px) { .tiktok-grid { grid-template-columns:repeat(4,1fr); } }
@media(max-width:768px) { .tiktok-grid { grid-template-columns:repeat(3,1fr); } }
@media(max-width:480px) { .tiktok-grid { grid-template-columns:repeat(2,1fr); } }

/* ===== AI赋能模块 ===== */
.ai-section { background:linear-gradient(135deg, #0a0a0a 0%, #1a0800 50%, #0a0a0a 100%); }
.ai-grid { display:grid; grid-template-columns:1fr 1fr; gap:48px; align-items:center; }
.ai-visual { position:relative; border-radius:var(--radius-lg); overflow:hidden; }
.ai-visual img { width:100%; height:360px; object-fit:cover; display:block; }
.ai-overlay { position:absolute; bottom:0; left:0; right:0; background:linear-gradient(transparent, rgba(0,0,0,.85)); padding:20px 16px 16px; }
.ai-overlay-text { color:var(--primary); font-size:.8rem; }
.ai-features { display:flex; flex-direction:column; gap:24px; }
.ai-feature-item { display:flex; gap:16px; align-items:flex-start; }
.ai-icon { font-size:1.8rem; flex-shrink:0; }
.ai-feature-title { color:#eee; font-size:.95rem; font-weight:600; margin-bottom:6px; }
.ai-feature-desc { color:#999; font-size:.84rem; line-height:1.7; }
@media(max-width:768px) { .ai-grid { grid-template-columns:1fr; } }

/* ===== 专家卡片横向布局 ===== */
@media(max-width:768px) {
  .expert-card[style*="flex-direction:row"] { flex-direction:column !important; }
}