/* ============================================
   困困兔 - 汽车改装视频社区 主样式文件
   Brand: KunKunTu | fjaek9.cn
   Version: 1.0
   ============================================ */

/* ---- CSS变量 ---- */
:root {
  --brand-orange: #E8500A;
  --brand-dark: #1A1D23;
  --brand-charcoal: #2C3040;
  --brand-mid: #3D4255;
  --brand-light: #F5F6FA;
  --brand-white: #FFFFFF;
  --brand-gray: #8A8FA8;
  --brand-border: #E2E5EF;
  --brand-orange-light: #FF6B2B;
  --brand-orange-dark: #C43D00;
  --font-main: 'PingFang SC', 'Microsoft YaHei', '微软雅黑', sans-serif;
  --radius-sm: 6px;
  --radius-md: 12px;
  --radius-lg: 20px;
  --shadow-sm: 0 2px 8px rgba(0,0,0,0.08);
  --shadow-md: 0 6px 24px rgba(0,0,0,0.12);
  --shadow-lg: 0 12px 40px rgba(0,0,0,0.18);
  --transition: all 0.3s ease;
}

/* ---- 全局重置 ---- */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; font-size: 16px; }
body {
  font-family: var(--font-main);
  background: var(--brand-light);
  color: var(--brand-dark);
  line-height: 1.7;
  overflow-x: hidden;
}
a { color: inherit; text-decoration: none; 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: var(--font-main); }

/* ---- 干扰标签隐藏 ---- */
.kkt-noise { display: none !important; visibility: hidden !important; }

/* ---- 布局容器 ---- */
.container { max-width: 1200px; margin: 0 auto; padding: 0 20px; }
.container-wide { max-width: 1400px; margin: 0 auto; padding: 0 20px; }

/* ============================================
   顶部公告栏
   ============================================ */
.top-bar {
  background: var(--brand-dark);
  color: rgba(255,255,255,0.75);
  font-size: 13px;
  padding: 6px 0;
  text-align: center;
}
.top-bar a { color: var(--brand-orange); }
.top-bar .top-bar-inner { display: flex; justify-content: space-between; align-items: center; }
.top-bar-links a { margin-left: 16px; }
.top-bar-links a:hover { color: var(--brand-white); }

/* ============================================
   头部导航
   ============================================ */
.site-header {
  background: var(--brand-white);
  box-shadow: var(--shadow-sm);
  position: sticky;
  top: 0;
  z-index: 1000;
}
.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 12px 0;
  gap: 20px;
}
.site-logo {
  display: flex;
  align-items: center;
  gap: 10px;
  flex-shrink: 0;
}
.site-logo img {
  width: 48px;
  height: 48px;
  object-fit: contain;
  border-radius: 8px;
}
.logo-text { display: flex; flex-direction: column; }
.logo-name {
  font-size: 22px;
  font-weight: 800;
  color: var(--brand-dark);
  letter-spacing: -0.5px;
  line-height: 1.1;
}
.logo-name span { color: var(--brand-orange); }
.logo-slogan {
  font-size: 11px;
  color: var(--brand-gray);
  letter-spacing: 0.5px;
}

/* 主导航 */
.main-nav { display: flex; align-items: center; gap: 4px; }
.main-nav a {
  padding: 8px 14px;
  font-size: 14px;
  font-weight: 500;
  color: var(--brand-charcoal);
  border-radius: var(--radius-sm);
  white-space: nowrap;
  position: relative;
}
.main-nav a::after {
  content: '';
  position: absolute;
  bottom: 4px;
  left: 50%;
  transform: translateX(-50%);
  width: 0;
  height: 2px;
  background: var(--brand-orange);
  transition: width 0.3s ease;
  border-radius: 2px;
}
.main-nav a:hover::after,
.main-nav a.active::after { width: 60%; }
.main-nav a:hover,
.main-nav a.active { color: var(--brand-orange); }

/* 搜索框 */
.header-search {
  display: flex;
  align-items: center;
  background: var(--brand-light);
  border: 1.5px solid var(--brand-border);
  border-radius: 24px;
  padding: 6px 16px;
  gap: 8px;
  min-width: 200px;
  transition: var(--transition);
}
.header-search:focus-within {
  border-color: var(--brand-orange);
  box-shadow: 0 0 0 3px rgba(232,80,10,0.1);
}
.header-search input {
  border: none;
  background: transparent;
  font-size: 14px;
  color: var(--brand-dark);
  outline: none;
  width: 100%;
  font-family: var(--font-main);
}
.header-search input::placeholder { color: var(--brand-gray); }
.search-btn {
  color: var(--brand-gray);
  font-size: 16px;
  transition: var(--transition);
  flex-shrink: 0;
}
.search-btn:hover { color: var(--brand-orange); }

/* 汉堡菜单 */
.hamburger {
  display: none;
  flex-direction: column;
  gap: 5px;
  padding: 8px;
  cursor: pointer;
}
.hamburger span {
  display: block;
  width: 24px;
  height: 2px;
  background: var(--brand-dark);
  border-radius: 2px;
  transition: var(--transition);
}

/* ============================================
   Hero 横幅
   ============================================ */
.hero-section {
  position: relative;
  overflow: hidden;
  min-height: 560px;
  display: flex;
  align-items: center;
}
.hero-bg {
  position: absolute;
  inset: 0;
  background-image: url('../images/hero-banner.jpg');
  background-size: cover;
  background-position: center;
  filter: brightness(0.55);
}
.hero-overlay {
  position: absolute;
  inset: 0;
  background: linear-gradient(135deg, rgba(26,29,35,0.85) 0%, rgba(232,80,10,0.25) 100%);
}
.hero-content {
  position: relative;
  z-index: 2;
  color: var(--brand-white);
  padding: 80px 0;
}
.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  background: rgba(232,80,10,0.9);
  color: white;
  padding: 4px 14px;
  border-radius: 20px;
  font-size: 12px;
  font-weight: 600;
  letter-spacing: 0.5px;
  margin-bottom: 16px;
}
.hero-title {
  font-size: clamp(32px, 5vw, 58px);
  font-weight: 900;
  line-height: 1.15;
  margin-bottom: 16px;
  letter-spacing: -1px;
}
.hero-title .brand { color: var(--brand-orange); }
.hero-subtitle {
  font-size: 18px;
  color: rgba(255,255,255,0.85);
  margin-bottom: 32px;
  max-width: 560px;
  line-height: 1.6;
}
.hero-stats {
  display: flex;
  gap: 32px;
  margin-bottom: 36px;
}
.hero-stat { text-align: center; }
.hero-stat .num {
  font-size: 28px;
  font-weight: 800;
  color: var(--brand-orange);
  display: block;
}
.hero-stat .label {
  font-size: 12px;
  color: rgba(255,255,255,0.7);
}
.hero-btns { display: flex; gap: 14px; flex-wrap: wrap; }
.btn-primary {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  background: var(--brand-orange);
  color: white;
  padding: 13px 28px;
  border-radius: var(--radius-md);
  font-size: 15px;
  font-weight: 700;
  transition: var(--transition);
  box-shadow: 0 4px 16px rgba(232,80,10,0.4);
}
.btn-primary:hover {
  background: var(--brand-orange-light);
  transform: translateY(-2px);
  box-shadow: 0 8px 24px rgba(232,80,10,0.5);
}
.btn-outline {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  background: transparent;
  color: white;
  padding: 13px 28px;
  border-radius: var(--radius-md);
  font-size: 15px;
  font-weight: 600;
  border: 2px solid rgba(255,255,255,0.5);
  transition: var(--transition);
}
.btn-outline:hover {
  border-color: white;
  background: rgba(255,255,255,0.1);
  transform: translateY(-2px);
}

/* ============================================
   通用区块样式
   ============================================ */
.section { padding: 70px 0; }
.section-alt { background: var(--brand-white); }
.section-dark { background: var(--brand-dark); color: var(--brand-white); }
.section-header { text-align: center; margin-bottom: 48px; }
.section-tag {
  display: inline-block;
  background: rgba(232,80,10,0.1);
  color: var(--brand-orange);
  padding: 4px 14px;
  border-radius: 20px;
  font-size: 12px;
  font-weight: 700;
  letter-spacing: 1px;
  text-transform: uppercase;
  margin-bottom: 12px;
}
.section-title {
  font-size: clamp(24px, 3vw, 36px);
  font-weight: 800;
  color: var(--brand-dark);
  margin-bottom: 12px;
  letter-spacing: -0.5px;
}
.section-dark .section-title { color: var(--brand-white); }
.section-desc {
  font-size: 16px;
  color: var(--brand-gray);
  max-width: 560px;
  margin: 0 auto;
}
.section-dark .section-desc { color: rgba(255,255,255,0.65); }

/* ============================================
   视频卡片
   ============================================ */
.video-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 24px;
}
.video-card {
  background: var(--brand-white);
  border-radius: var(--radius-md);
  overflow: hidden;
  box-shadow: var(--shadow-sm);
  transition: var(--transition);
}
.video-card:hover {
  transform: translateY(-6px);
  box-shadow: var(--shadow-md);
}
.video-thumb {
  position: relative;
  aspect-ratio: 16/9;
  overflow: hidden;
  background: var(--brand-charcoal);
  cursor: pointer;
}
.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);
  transition: background 0.3s ease;
}
.video-card:hover .play-btn { background: rgba(0,0,0,0.35); }
.play-icon {
  width: 52px;
  height: 52px;
  background: var(--brand-orange);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  opacity: 0;
  transform: scale(0.7);
  transition: all 0.3s ease;
  box-shadow: 0 4px 16px rgba(232,80,10,0.5);
}
.video-card:hover .play-icon {
  opacity: 1;
  transform: scale(1);
}
.play-icon::after {
  content: '';
  border-style: solid;
  border-width: 10px 0 10px 18px;
  border-color: transparent transparent transparent white;
  margin-left: 4px;
}
.video-duration {
  position: absolute;
  bottom: 8px;
  right: 8px;
  background: rgba(0,0,0,0.75);
  color: white;
  font-size: 12px;
  padding: 2px 7px;
  border-radius: 4px;
  font-weight: 600;
}
.video-quality {
  position: absolute;
  top: 8px;
  left: 8px;
  background: var(--brand-orange);
  color: white;
  font-size: 11px;
  padding: 2px 7px;
  border-radius: 4px;
  font-weight: 700;
}
.video-info { padding: 14px 16px; }
.video-title {
  font-size: 14px;
  font-weight: 700;
  color: var(--brand-dark);
  margin-bottom: 8px;
  line-height: 1.4;
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
}
.video-meta {
  display: flex;
  align-items: center;
  justify-content: space-between;
  font-size: 12px;
  color: var(--brand-gray);
}
.video-stats { display: flex; gap: 12px; align-items: center; }
.video-stats span { display: flex; align-items: center; gap: 4px; }
.video-category {
  background: rgba(232,80,10,0.1);
  color: var(--brand-orange);
  padding: 2px 8px;
  border-radius: 4px;
  font-size: 11px;
  font-weight: 600;
}

/* ============================================
   特色模块卡片
   ============================================ */
.feature-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(240px, 1fr));
  gap: 24px;
}
.feature-card {
  background: var(--brand-white);
  border-radius: var(--radius-md);
  padding: 28px 24px;
  box-shadow: var(--shadow-sm);
  transition: var(--transition);
  border: 1.5px solid transparent;
}
.feature-card:hover {
  border-color: var(--brand-orange);
  transform: translateY(-4px);
  box-shadow: var(--shadow-md);
}
.feature-icon {
  width: 52px;
  height: 52px;
  background: linear-gradient(135deg, var(--brand-orange), var(--brand-orange-light));
  border-radius: var(--radius-md);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 24px;
  margin-bottom: 16px;
}
.feature-title {
  font-size: 16px;
  font-weight: 700;
  color: var(--brand-dark);
  margin-bottom: 8px;
}
.feature-desc {
  font-size: 13px;
  color: var(--brand-gray);
  line-height: 1.6;
}

/* ============================================
   专家展示
   ============================================ */
.expert-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
  gap: 28px;
}
.expert-card {
  background: var(--brand-white);
  border-radius: var(--radius-lg);
  overflow: hidden;
  box-shadow: var(--shadow-sm);
  transition: var(--transition);
}
.expert-card:hover { transform: translateY(-6px); box-shadow: var(--shadow-md); }
.expert-photo {
  position: relative;
  height: 240px;
  overflow: hidden;
}
.expert-photo img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  object-position: top;
  transition: transform 0.4s ease;
}
.expert-card:hover .expert-photo img { transform: scale(1.05); }
.expert-badge {
  position: absolute;
  top: 12px;
  right: 12px;
  background: var(--brand-orange);
  color: white;
  font-size: 11px;
  font-weight: 700;
  padding: 3px 10px;
  border-radius: 20px;
}
.expert-info { padding: 20px; }
.expert-name {
  font-size: 18px;
  font-weight: 800;
  color: var(--brand-dark);
  margin-bottom: 4px;
}
.expert-title {
  font-size: 13px;
  color: var(--brand-orange);
  font-weight: 600;
  margin-bottom: 10px;
}
.expert-desc {
  font-size: 13px;
  color: var(--brand-gray);
  line-height: 1.6;
  margin-bottom: 14px;
}
.expert-awards {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  margin-bottom: 14px;
}
.award-tag {
  background: var(--brand-light);
  color: var(--brand-charcoal);
  font-size: 11px;
  padding: 3px 8px;
  border-radius: 4px;
  font-weight: 500;
}
.expert-btns { display: flex; gap: 10px; }
.btn-sm {
  flex: 1;
  text-align: center;
  padding: 8px 12px;
  border-radius: var(--radius-sm);
  font-size: 13px;
  font-weight: 600;
  transition: var(--transition);
}
.btn-sm-primary {
  background: var(--brand-orange);
  color: white;
}
.btn-sm-primary:hover { background: var(--brand-orange-light); }
.btn-sm-outline {
  border: 1.5px solid var(--brand-border);
  color: var(--brand-charcoal);
}
.btn-sm-outline:hover { border-color: var(--brand-orange); color: var(--brand-orange); }

/* ============================================
   用户评价
   ============================================ */
.reviews-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
  gap: 24px;
}
.review-card {
  background: var(--brand-white);
  border-radius: var(--radius-md);
  padding: 24px;
  box-shadow: var(--shadow-sm);
  transition: var(--transition);
  border-left: 4px solid var(--brand-orange);
}
.review-card:hover { transform: translateY(-3px); box-shadow: var(--shadow-md); }
.review-stars { color: #FFB800; font-size: 16px; margin-bottom: 10px; }
.review-text {
  font-size: 14px;
  color: var(--brand-charcoal);
  line-height: 1.7;
  margin-bottom: 16px;
  font-style: italic;
}
.review-author { display: flex; align-items: center; gap: 12px; }
.review-avatar {
  width: 40px;
  height: 40px;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--brand-orange), var(--brand-orange-light));
  display: flex;
  align-items: center;
  justify-content: center;
  color: white;
  font-weight: 700;
  font-size: 16px;
  flex-shrink: 0;
}
.review-name { font-size: 14px; font-weight: 700; color: var(--brand-dark); }
.review-info { font-size: 12px; color: var(--brand-gray); }

/* ============================================
   FAQ
   ============================================ */
.faq-list { max-width: 800px; margin: 0 auto; }
.faq-item {
  background: var(--brand-white);
  border-radius: var(--radius-md);
  margin-bottom: 12px;
  box-shadow: var(--shadow-sm);
  overflow: hidden;
}
.faq-question {
  padding: 18px 24px;
  font-size: 15px;
  font-weight: 700;
  color: var(--brand-dark);
  cursor: pointer;
  display: flex;
  justify-content: space-between;
  align-items: center;
  transition: var(--transition);
}
.faq-question:hover { color: var(--brand-orange); }
.faq-question .faq-icon {
  width: 24px;
  height: 24px;
  border-radius: 50%;
  background: var(--brand-light);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 16px;
  color: var(--brand-orange);
  transition: transform 0.3s ease;
  flex-shrink: 0;
}
.faq-item.open .faq-icon { transform: rotate(45deg); }
.faq-answer {
  padding: 0 24px;
  font-size: 14px;
  color: var(--brand-gray);
  line-height: 1.7;
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.4s ease, padding 0.3s ease;
}
.faq-item.open .faq-answer {
  max-height: 300px;
  padding: 0 24px 18px;
}

/* ============================================
   合作品牌 Logo 墙
   ============================================ */
.partner-grid {
  display: flex;
  flex-wrap: wrap;
  gap: 16px;
  justify-content: center;
  align-items: center;
}
.partner-item {
  background: var(--brand-white);
  border: 1.5px solid var(--brand-border);
  border-radius: var(--radius-md);
  padding: 16px 24px;
  font-size: 15px;
  font-weight: 700;
  color: var(--brand-charcoal);
  transition: var(--transition);
  min-width: 120px;
  text-align: center;
}
.partner-item:hover {
  border-color: var(--brand-orange);
  color: var(--brand-orange);
  transform: translateY(-3px);
  box-shadow: var(--shadow-sm);
}

/* ============================================
   联系我们
   ============================================ */
.contact-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 40px;
  align-items: start;
}
.contact-info-block { }
.contact-item {
  display: flex;
  gap: 16px;
  margin-bottom: 24px;
  align-items: flex-start;
}
.contact-icon {
  width: 44px;
  height: 44px;
  background: rgba(232,80,10,0.1);
  border-radius: var(--radius-sm);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 20px;
  flex-shrink: 0;
}
.contact-label {
  font-size: 12px;
  color: var(--brand-gray);
  margin-bottom: 4px;
}
.contact-value {
  font-size: 15px;
  font-weight: 600;
  color: var(--brand-dark);
}
.qr-row {
  display: flex;
  gap: 24px;
  flex-wrap: wrap;
}
.qr-block { text-align: center; }
.qr-block img {
  width: 120px;
  height: 120px;
  border-radius: var(--radius-sm);
  border: 2px solid var(--brand-border);
  margin-bottom: 8px;
}
.qr-label {
  font-size: 12px;
  color: var(--brand-gray);
  font-weight: 500;
}

/* ============================================
   社区加入指南
   ============================================ */
.join-steps {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
  gap: 24px;
  counter-reset: step;
}
.join-step {
  background: var(--brand-white);
  border-radius: var(--radius-md);
  padding: 24px 20px;
  text-align: center;
  box-shadow: var(--shadow-sm);
  position: relative;
  transition: var(--transition);
}
.join-step:hover { transform: translateY(-4px); box-shadow: var(--shadow-md); }
.step-num {
  width: 40px;
  height: 40px;
  background: var(--brand-orange);
  color: white;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 18px;
  font-weight: 800;
  margin: 0 auto 14px;
}
.step-title {
  font-size: 15px;
  font-weight: 700;
  color: var(--brand-dark);
  margin-bottom: 8px;
}
.step-desc { font-size: 13px; color: var(--brand-gray); line-height: 1.6; }

/* ============================================
   社交分享
   ============================================ */
.share-bar {
  display: flex;
  align-items: center;
  gap: 12px;
  flex-wrap: wrap;
}
.share-label {
  font-size: 14px;
  color: var(--brand-gray);
  font-weight: 600;
}
.share-btn {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 7px 16px;
  border-radius: 20px;
  font-size: 13px;
  font-weight: 600;
  transition: var(--transition);
  cursor: pointer;
}
.share-wechat { background: #07C160; color: white; }
.share-weibo { background: #E6162D; color: white; }
.share-douyin { background: #000000; color: white; }
.share-bilibili { background: #00A1D6; color: white; }
.share-btn:hover { opacity: 0.85; transform: translateY(-2px); }

/* ============================================
   AI 赋能模块
   ============================================ */
.ai-section {
  background: linear-gradient(135deg, var(--brand-dark) 0%, var(--brand-charcoal) 100%);
  color: var(--brand-white);
  position: relative;
  overflow: hidden;
}
.ai-section::before {
  content: '';
  position: absolute;
  top: -50%;
  right: -10%;
  width: 500px;
  height: 500px;
  background: radial-gradient(circle, rgba(232,80,10,0.15) 0%, transparent 70%);
  pointer-events: none;
}
.ai-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 60px;
  align-items: center;
}
.ai-features { display: flex; flex-direction: column; gap: 20px; }
.ai-feature-item {
  display: flex;
  gap: 16px;
  align-items: flex-start;
}
.ai-feature-icon {
  width: 44px;
  height: 44px;
  background: rgba(232,80,10,0.2);
  border: 1.5px solid rgba(232,80,10,0.4);
  border-radius: var(--radius-sm);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 20px;
  flex-shrink: 0;
}
.ai-feature-title {
  font-size: 15px;
  font-weight: 700;
  color: var(--brand-white);
  margin-bottom: 4px;
}
.ai-feature-desc { font-size: 13px; color: rgba(255,255,255,0.65); line-height: 1.6; }
.ai-image-wrap {
  border-radius: var(--radius-lg);
  overflow: hidden;
  box-shadow: var(--shadow-lg);
}
.ai-image-wrap img { width: 100%; height: 320px; object-fit: cover; }

/* ============================================
   底部
   ============================================ */
.site-footer {
  background: var(--brand-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 {}
.footer-logo {
  display: flex;
  align-items: center;
  gap: 10px;
  margin-bottom: 16px;
}
.footer-logo img {
  width: 40px;
  height: 40px;
  object-fit: contain;
  border-radius: 6px;
}
.footer-logo-name {
  font-size: 20px;
  font-weight: 800;
  color: var(--brand-white);
}
.footer-logo-name span { color: var(--brand-orange); }
.footer-desc {
  font-size: 13px;
  line-height: 1.7;
  margin-bottom: 20px;
  color: rgba(255,255,255,0.6);
}
.footer-social { display: flex; gap: 10px; }
.social-icon {
  width: 36px;
  height: 36px;
  background: rgba(255,255,255,0.08);
  border-radius: 8px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 16px;
  transition: var(--transition);
}
.social-icon:hover { background: var(--brand-orange); }
.footer-col-title {
  font-size: 14px;
  font-weight: 700;
  color: var(--brand-white);
  margin-bottom: 16px;
  padding-bottom: 8px;
  border-bottom: 1px solid rgba(255,255,255,0.1);
}
.footer-links { display: flex; flex-direction: column; gap: 8px; }
.footer-links a {
  font-size: 13px;
  color: rgba(255,255,255,0.6);
  transition: var(--transition);
}
.footer-links a:hover { color: var(--brand-orange); padding-left: 4px; }
.footer-bottom {
  border-top: 1px solid rgba(255,255,255,0.1);
  padding: 20px 0;
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 12px;
}
.footer-copy { font-size: 13px; color: rgba(255,255,255,0.5); }
.footer-copy a { color: var(--brand-orange); }
.footer-update { font-size: 12px; color: rgba(255,255,255,0.4); }
.footer-links-bottom { display: flex; gap: 16px; }
.footer-links-bottom a {
  font-size: 12px;
  color: rgba(255,255,255,0.5);
  transition: var(--transition);
}
.footer-links-bottom a:hover { color: var(--brand-orange); }

/* ============================================
   面包屑
   ============================================ */
.breadcrumb {
  background: var(--brand-white);
  padding: 12px 0;
  border-bottom: 1px solid var(--brand-border);
}
.breadcrumb-list {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 13px;
  color: var(--brand-gray);
}
.breadcrumb-list a { color: var(--brand-gray); }
.breadcrumb-list a:hover { color: var(--brand-orange); }
.breadcrumb-list .sep { color: var(--brand-border); }
.breadcrumb-list .current { color: var(--brand-dark); font-weight: 600; }

/* ============================================
   内页 Banner
   ============================================ */
.page-banner {
  background: linear-gradient(135deg, var(--brand-dark) 0%, var(--brand-charcoal) 100%);
  padding: 60px 0;
  color: var(--brand-white);
  position: relative;
  overflow: hidden;
}
.page-banner::after {
  content: '';
  position: absolute;
  right: 0;
  top: 0;
  bottom: 0;
  width: 40%;
  background: linear-gradient(90deg, transparent, rgba(232,80,10,0.1));
  pointer-events: none;
}
.page-banner h1 {
  font-size: clamp(28px, 4vw, 44px);
  font-weight: 900;
  margin-bottom: 10px;
  letter-spacing: -0.5px;
}
.page-banner p {
  font-size: 16px;
  color: rgba(255,255,255,0.7);
  max-width: 560px;
}

/* ============================================
   标签页
   ============================================ */
.tab-nav {
  display: flex;
  gap: 4px;
  background: var(--brand-light);
  padding: 4px;
  border-radius: var(--radius-md);
  margin-bottom: 32px;
  overflow-x: auto;
}
.tab-btn {
  padding: 9px 20px;
  border-radius: var(--radius-sm);
  font-size: 14px;
  font-weight: 600;
  color: var(--brand-gray);
  white-space: nowrap;
  transition: var(--transition);
  cursor: pointer;
}
.tab-btn.active,
.tab-btn:hover {
  background: var(--brand-white);
  color: var(--brand-orange);
  box-shadow: var(--shadow-sm);
}

/* ============================================
   统计数字
   ============================================ */
.stats-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 24px;
}
.stat-card {
  background: var(--brand-white);
  border-radius: var(--radius-md);
  padding: 28px 20px;
  text-align: center;
  box-shadow: var(--shadow-sm);
  transition: var(--transition);
}
.stat-card:hover { transform: translateY(-4px); box-shadow: var(--shadow-md); }
.stat-num {
  font-size: 36px;
  font-weight: 900;
  color: var(--brand-orange);
  line-height: 1;
  margin-bottom: 8px;
}
.stat-label {
  font-size: 13px;
  color: var(--brand-gray);
  font-weight: 500;
}

/* ============================================
   搜索结果提示
   ============================================ */
#search-modal {
  display: none;
  position: fixed;
  inset: 0;
  background: rgba(0,0,0,0.5);
  z-index: 9999;
  align-items: flex-start;
  justify-content: center;
  padding-top: 80px;
}
#search-modal.show { display: flex; }
.search-modal-box {
  background: var(--brand-white);
  border-radius: var(--radius-lg);
  padding: 24px;
  width: 90%;
  max-width: 560px;
  box-shadow: var(--shadow-lg);
}
.search-modal-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 16px;
}
.search-modal-title { font-size: 16px; font-weight: 700; }
.search-modal-close {
  width: 28px;
  height: 28px;
  background: var(--brand-light);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  font-size: 16px;
  color: var(--brand-gray);
}
.search-modal-close:hover { background: var(--brand-orange); color: white; }
.search-tips {
  font-size: 13px;
  color: var(--brand-gray);
  line-height: 1.7;
  padding: 16px;
  background: var(--brand-light);
  border-radius: var(--radius-sm);
}

/* ============================================
   响应式
   ============================================ */
@media (max-width: 1024px) {
  .footer-grid { grid-template-columns: 1fr 1fr; }
  .ai-grid { grid-template-columns: 1fr; }
  .ai-image-wrap { display: none; }
  .stats-grid { grid-template-columns: repeat(2, 1fr); }
  .contact-grid { grid-template-columns: 1fr; }
}

@media (max-width: 768px) {
  .main-nav { display: none; }
  .main-nav.open {
    display: flex;
    flex-direction: column;
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    background: var(--brand-white);
    box-shadow: var(--shadow-md);
    padding: 16px;
    gap: 4px;
    z-index: 999;
  }
  .hamburger { display: flex; }
  .header-search { min-width: 140px; }
  .hero-stats { gap: 20px; }
  .hero-stat .num { font-size: 22px; }
  .footer-grid { grid-template-columns: 1fr; }
  .footer-bottom { flex-direction: column; text-align: center; }
  .video-grid { grid-template-columns: repeat(auto-fill, minmax(240px, 1fr)); }
  .expert-grid { grid-template-columns: 1fr; }
  .reviews-grid { grid-template-columns: 1fr; }
  .stats-grid { grid-template-columns: repeat(2, 1fr); }
  .top-bar .top-bar-inner { flex-direction: column; gap: 4px; }
}

@media (max-width: 480px) {
  .container { padding: 0 14px; }
  .section { padding: 48px 0; }
  .hero-section { min-height: 420px; }
  .hero-content { padding: 50px 0; }
  .hero-btns { flex-direction: column; }
  .stats-grid { grid-template-columns: 1fr 1fr; }
  .join-steps { grid-template-columns: 1fr 1fr; }
  .feature-grid { grid-template-columns: 1fr 1fr; }
  .qr-row { justify-content: center; }
}

/* ============================================
   加载动画
   ============================================ */
.lazy-img {
  opacity: 0;
  transition: opacity 0.4s ease;
}
.lazy-img.loaded { opacity: 1; }

/* ============================================
   滚动条美化
   ============================================ */
::-webkit-scrollbar { width: 6px; height: 6px; }
::-webkit-scrollbar-track { background: var(--brand-light); }
::-webkit-scrollbar-thumb { background: var(--brand-border); border-radius: 3px; }
::-webkit-scrollbar-thumb:hover { background: var(--brand-orange); }

/* ============================================
   视频播放器模态框
   ============================================ */
#video-modal {
  display: none;
  position: fixed;
  inset: 0;
  background: rgba(0,0,0,0.85);
  z-index: 9999;
  align-items: center;
  justify-content: center;
}
#video-modal.show { display: flex; }
.video-modal-box {
  background: #000;
  border-radius: var(--radius-md);
  width: 90%;
  max-width: 800px;
  aspect-ratio: 16/9;
  position: relative;
  overflow: hidden;
}
.video-modal-close {
  position: absolute;
  top: 12px;
  right: 12px;
  width: 32px;
  height: 32px;
  background: rgba(255,255,255,0.2);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  color: white;
  font-size: 18px;
  z-index: 10;
  transition: var(--transition);
}
.video-modal-close:hover { background: var(--brand-orange); }
.video-placeholder {
  width: 100%;
  height: 100%;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  color: white;
  gap: 16px;
}
.video-placeholder .play-big {
  width: 80px;
  height: 80px;
  background: var(--brand-orange);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
}
.video-placeholder .play-big::after {
  content: '';
  border-style: solid;
  border-width: 16px 0 16px 28px;
  border-color: transparent transparent transparent white;
  margin-left: 6px;
}
.video-placeholder p { font-size: 16px; color: rgba(255,255,255,0.7); }

/* ============================================
   联系页面补充样式
   ============================================ */
.contact-layout {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 48px;
  align-items: start;
}
.contact-cards { display: grid; gap: 12px; margin-bottom: 28px; }
.contact-card {
  display: flex;
  align-items: center;
  gap: 14px;
  background: var(--brand-light);
  border-radius: var(--radius-md);
  padding: 14px 18px;
  border: 1.5px solid var(--brand-border);
  transition: var(--transition);
}
.contact-card:hover { border-color: var(--brand-orange); }
.contact-detail .contact-label { font-size: 12px; color: var(--brand-gray); margin-bottom: 2px; }
.contact-detail .contact-value { font-size: 15px; font-weight: 600; color: var(--brand-dark); }
.qr-codes { display: flex; gap: 24px; }
.qr-item { text-align: center; }
.qr-item img { border-radius: var(--radius-sm); border: 2px solid var(--brand-border); margin-bottom: 8px; }
.qr-item p { font-size: 12px; color: var(--brand-gray); }
.contact-form-wrap {
  background: var(--brand-white);
  border-radius: var(--radius-lg);
  padding: 36px 32px;
  box-shadow: var(--shadow-md);
  border: 1.5px solid var(--brand-border);
}
.form-title { font-size: 20px; font-weight: 800; color: var(--brand-dark); margin-bottom: 24px; }
.form-group { margin-bottom: 18px; }
.form-group label { display: block; font-size: 13px; font-weight: 600; color: var(--brand-charcoal); margin-bottom: 6px; }
.form-input, .form-textarea {
  width: 100%;
  padding: 11px 14px;
  border: 1.5px solid var(--brand-border);
  border-radius: var(--radius-sm);
  font-size: 14px;
  color: var(--brand-dark);
  background: var(--brand-white);
  transition: var(--transition);
  font-family: var(--font-main);
  outline: none;
}
.form-input:focus, .form-textarea:focus { border-color: var(--brand-orange); box-shadow: 0 0 0 3px rgba(232,80,10,0.1); }
.form-textarea { resize: vertical; }
.form-submit {
  width: 100%;
  background: var(--brand-orange);
  color: white;
  padding: 13px;
  border-radius: var(--radius-md);
  font-size: 15px;
  font-weight: 700;
  transition: var(--transition);
  cursor: pointer;
  border: none;
  font-family: var(--font-main);
}
.form-submit:hover { background: var(--brand-orange-light); transform: translateY(-2px); }
@media (max-width: 768px) {
  .contact-layout { grid-template-columns: 1fr; }
}

/* ============================================
   跑马灯
   ============================================ */
.marquee-wrap {
  background: var(--brand-orange);
  padding: 9px 0;
  overflow: hidden;
}
.marquee-inner {
  display: flex;
  gap: 48px;
  white-space: nowrap;
  animation: marquee 35s linear infinite;
}
.marquee-inner span { color: white; font-size: 13px; font-weight: 600; }
@keyframes marquee {
  from { transform: translateX(0); }
  to { transform: translateX(-50%); }
}

/* ============================================
   AI 卡片补充
   ============================================ */
.ai-card-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 24px;
}
.ai-card-item {
  background: rgba(255,255,255,0.06);
  border: 1.5px solid rgba(255,255,255,0.12);
  border-radius: var(--radius-md);
  padding: 28px 24px;
  transition: var(--transition);
}
.ai-card-item:hover {
  background: rgba(255,255,255,0.1);
  border-color: var(--brand-orange);
  transform: translateY(-4px);
}
.ai-card-item .feature-title { color: var(--brand-white); }
.ai-card-item .feature-desc { color: rgba(255,255,255,0.6); }

/* ============================================
   专家头像补充
   ============================================ */
.expert-avatar-circle {
  width: 80px;
  height: 80px;
  border-radius: 50%;
  object-fit: cover;
  margin: 0 auto 16px;
  border: 3px solid var(--brand-orange);
  display: block;
}