/* ========================================
   蜜桃传媒 - 汽车改装与视频社区
   原创配色：深夜蓝 + 燃橙 + 碳纤维灰
   bvvsbxgc.cn
   ======================================== */

:root {
  --brand-primary: #ff6b1a;
  --brand-secondary: #0d1f3c;
  --brand-accent: #e8a020;
  --bg-dark: #080f1e;
  --bg-card: #111827;
  --bg-card2: #1a2540;
  --bg-section: #0d1628;
  --text-main: #e8edf5;
  --text-muted: #8a9bb8;
  --text-light: #c4cfdf;
  --border-color: rgba(255,107,26,0.18);
  --border-subtle: rgba(255,255,255,0.07);
  --radius-sm: 8px;
  --radius-md: 14px;
  --radius-lg: 22px;
  --shadow-card: 0 4px 24px rgba(0,0,0,0.45);
  --shadow-glow: 0 0 32px rgba(255,107,26,0.22);
  --transition: 0.28s cubic-bezier(.4,0,.2,1);
  --font-main: 'PingFang SC','Microsoft YaHei','Helvetica Neue',sans-serif;
}

*, *::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-main);
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
}

a { color: var(--brand-primary); text-decoration: none; transition: color var(--transition); }
a:hover { color: var(--brand-accent); }

img { max-width: 100%; height: auto; display: block; }

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

/* ---- 公告栏 ---- */
.notice-bar {
  background: linear-gradient(90deg, #ff6b1a 0%, #e8a020 50%, #ff6b1a 100%);
  background-size: 200% 100%;
  animation: noticeSlide 4s linear infinite;
  color: #fff;
  font-size: 13px;
  font-weight: 600;
  text-align: center;
  padding: 8px 16px;
  letter-spacing: 0.5px;
}
.notice-bar a { color: #fff; text-decoration: underline; margin: 0 8px; }
@keyframes noticeSlide { 0%{background-position:0% 50%} 100%{background-position:200% 50%} }

/* ---- 顶部导航 ---- */
.site-header {
  position: sticky;
  top: 0;
  z-index: 1000;
  background: rgba(8,15,30,0.96);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border-color);
  box-shadow: 0 2px 20px rgba(0,0,0,0.4);
}
.header-inner {
  max-width: 1280px;
  margin: 0 auto;
  padding: 0 24px;
  height: 68px;
  display: flex;
  align-items: center;
  gap: 24px;
}
.site-logo {
  display: flex;
  align-items: center;
  gap: 10px;
  flex-shrink: 0;
  text-decoration: none;
}
.site-logo .logo-icon {
  width: 38px;
  height: 38px;
  border-radius: 10px;
  object-fit: contain;
  background: var(--bg-card2);
  padding: 3px;
}
.site-logo .logo-text {
  font-size: 20px;
  font-weight: 800;
  color: #fff;
  letter-spacing: -0.5px;
}
.site-logo .logo-text span { color: var(--brand-primary); }

.main-nav {
  display: flex;
  align-items: center;
  gap: 4px;
  flex: 1;
}
.main-nav a {
  color: var(--text-light);
  font-size: 14px;
  font-weight: 500;
  padding: 6px 13px;
  border-radius: var(--radius-sm);
  transition: all var(--transition);
  white-space: nowrap;
}
.main-nav a:hover, .main-nav a.active {
  color: var(--brand-primary);
  background: rgba(255,107,26,0.1);
}

/* ---- 搜索框 ---- */
.header-search {
  display: flex;
  align-items: center;
  background: var(--bg-card2);
  border: 1px solid var(--border-color);
  border-radius: 24px;
  overflow: hidden;
  transition: border-color var(--transition);
  flex-shrink: 0;
}
.header-search:focus-within { border-color: var(--brand-primary); }
.header-search input {
  background: none;
  border: none;
  outline: none;
  color: var(--text-main);
  font-size: 13px;
  padding: 8px 14px;
  width: 180px;
}
.header-search input::placeholder { color: var(--text-muted); }
.header-search button {
  background: var(--brand-primary);
  border: none;
  color: #fff;
  padding: 8px 14px;
  cursor: pointer;
  font-size: 14px;
  transition: background var(--transition);
}
.header-search button:hover { background: var(--brand-accent); }

/* ---- 移动端菜单 ---- */
.mobile-toggle {
  display: none;
  background: none;
  border: 1px solid var(--border-color);
  color: var(--text-main);
  font-size: 20px;
  padding: 6px 10px;
  border-radius: var(--radius-sm);
  cursor: pointer;
  margin-left: auto;
}
.mobile-nav {
  display: none;
  background: var(--bg-card);
  border-top: 1px solid var(--border-color);
  padding: 12px 24px;
  flex-direction: column;
  gap: 4px;
}
.mobile-nav.open { display: flex; }
.mobile-nav a {
  color: var(--text-light);
  font-size: 15px;
  padding: 10px 0;
  border-bottom: 1px solid var(--border-subtle);
}

/* ---- 容器 ---- */
.container { max-width: 1280px; margin: 0 auto; padding: 0 24px; }

/* ---- 通用区块 ---- */
.section { padding: 80px 0; }
.section-alt { background: var(--bg-section); }
.section-header { text-align: center; margin-bottom: 52px; }
.section-label {
  display: inline-block;
  background: rgba(255,107,26,0.12);
  color: var(--brand-primary);
  font-size: 12px;
  font-weight: 700;
  letter-spacing: 1.5px;
  text-transform: uppercase;
  padding: 5px 14px;
  border-radius: 20px;
  border: 1px solid rgba(255,107,26,0.3);
  margin-bottom: 16px;
}
.section-title {
  font-size: clamp(26px, 4vw, 38px);
  font-weight: 800;
  color: #fff;
  line-height: 1.25;
  margin-bottom: 14px;
}
.section-title .hl { color: var(--brand-primary); }
.section-desc {
  font-size: 16px;
  color: var(--text-muted);
  max-width: 600px;
  margin: 0 auto;
  line-height: 1.8;
}

/* ---- 英雄Banner ---- */
.hero-section {
  position: relative;
  min-height: 92vh;
  display: flex;
  align-items: center;
  overflow: hidden;
}
.hero-bg {
  position: absolute;
  inset: 0;
  background-image: url('/images/banner-hero.jpg');
  background-size: cover;
  background-position: center;
  filter: brightness(0.32);
  transform: scale(1.04);
  transition: transform 8s ease;
}
.hero-bg.loaded { transform: scale(1); }
.hero-overlay {
  position: absolute;
  inset: 0;
  background: linear-gradient(135deg, rgba(8,15,30,0.85) 0%, rgba(13,31,60,0.6) 50%, rgba(255,107,26,0.08) 100%);
}
.hero-content {
  position: relative;
  z-index: 2;
  max-width: 760px;
  padding: 60px 24px;
  margin-left: calc((100vw - 1280px)/2 + 24px);
}
.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  background: rgba(255,107,26,0.15);
  border: 1px solid rgba(255,107,26,0.4);
  color: var(--brand-primary);
  font-size: 13px;
  font-weight: 600;
  padding: 6px 16px;
  border-radius: 20px;
  margin-bottom: 24px;
}
.hero-badge::before { content: '🏎'; font-size: 16px; }
.hero-h1 {
  font-size: clamp(36px, 6vw, 68px);
  font-weight: 900;
  color: #fff;
  line-height: 1.12;
  margin-bottom: 20px;
  letter-spacing: -1px;
}
.hero-h1 .hl {
  color: var(--brand-primary);
  text-shadow: 0 0 40px rgba(255,107,26,0.5);
}
.hero-sub {
  font-size: 18px;
  color: var(--text-light);
  margin-bottom: 36px;
  line-height: 1.7;
  max-width: 580px;
}
.hero-btns {
  display: flex;
  gap: 14px;
  flex-wrap: wrap;
}
.btn-primary {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  background: var(--brand-primary);
  color: #fff;
  font-size: 15px;
  font-weight: 700;
  padding: 14px 30px;
  border-radius: var(--radius-md);
  transition: all var(--transition);
  box-shadow: 0 4px 20px rgba(255,107,26,0.4);
}
.btn-primary:hover {
  background: var(--brand-accent);
  color: #fff;
  transform: translateY(-2px);
  box-shadow: 0 8px 30px rgba(255,107,26,0.5);
}
.btn-outline {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  background: transparent;
  color: #fff;
  font-size: 15px;
  font-weight: 600;
  padding: 13px 28px;
  border-radius: var(--radius-md);
  border: 2px solid rgba(255,255,255,0.3);
  transition: all var(--transition);
}
.btn-outline:hover {
  border-color: var(--brand-primary);
  color: var(--brand-primary);
  background: rgba(255,107,26,0.08);
}

/* ---- 数据统计 ---- */
.stats-strip {
  background: var(--bg-card2);
  border-top: 1px solid var(--border-color);
  border-bottom: 1px solid var(--border-color);
  padding: 32px 0;
}
.stats-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 0;
}
.stat-item {
  text-align: center;
  padding: 16px 24px;
  border-right: 1px solid var(--border-subtle);
}
.stat-item:last-child { border-right: none; }
.stat-num {
  font-size: 38px;
  font-weight: 900;
  color: var(--brand-primary);
  line-height: 1;
  margin-bottom: 6px;
}
.stat-num sup { font-size: 18px; }
.stat-label { font-size: 13px; color: var(--text-muted); }

/* ---- 视频卡片网格 ---- */
.video-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 20px;
}
.video-grid-3 { grid-template-columns: repeat(3, 1fr); }
.video-grid-2 { grid-template-columns: repeat(2, 1fr); }

.video-card {
  background: var(--bg-card);
  border-radius: var(--radius-md);
  overflow: hidden;
  border: 1px solid var(--border-subtle);
  transition: all var(--transition);
  cursor: pointer;
}
.video-card:hover {
  transform: translateY(-5px);
  border-color: var(--border-color);
  box-shadow: var(--shadow-glow);
}
.video-thumb {
  position: relative;
  aspect-ratio: 16/9;
  overflow: hidden;
  background: var(--bg-card2);
}
.video-thumb img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform 0.5s ease;
}
.video-card:hover .video-thumb img { transform: scale(1.06); }
.play-overlay {
  position: absolute;
  inset: 0;
  background: rgba(0,0,0,0.35);
  display: flex;
  align-items: center;
  justify-content: center;
  opacity: 0;
  transition: opacity var(--transition);
}
.video-card:hover .play-overlay { opacity: 1; }
.play-btn {
  width: 52px;
  height: 52px;
  background: var(--brand-primary);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  box-shadow: 0 4px 20px rgba(255,107,26,0.6);
  transition: transform var(--transition);
}
.play-btn::after {
  content: '';
  border-left: 18px solid #fff;
  border-top: 11px solid transparent;
  border-bottom: 11px solid transparent;
  margin-left: 4px;
}
.play-btn:hover { transform: scale(1.1); }
.video-badge {
  position: absolute;
  top: 10px;
  left: 10px;
  background: var(--brand-primary);
  color: #fff;
  font-size: 11px;
  font-weight: 700;
  padding: 3px 9px;
  border-radius: 4px;
}
.video-duration {
  position: absolute;
  bottom: 8px;
  right: 8px;
  background: rgba(0,0,0,0.75);
  color: #fff;
  font-size: 11px;
  padding: 2px 7px;
  border-radius: 4px;
}
.video-info { padding: 14px; }
.video-title {
  font-size: 14px;
  font-weight: 600;
  color: var(--text-main);
  line-height: 1.5;
  margin-bottom: 8px;
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
}
.video-meta {
  display: flex;
  align-items: center;
  gap: 12px;
  font-size: 12px;
  color: var(--text-muted);
  margin-bottom: 8px;
}
.video-tags { display: flex; gap: 6px; flex-wrap: wrap; }
.vtag {
  font-size: 11px;
  color: var(--brand-primary);
  background: rgba(255,107,26,0.1);
  border: 1px solid rgba(255,107,26,0.2);
  padding: 2px 8px;
  border-radius: 4px;
}

/* ---- 功能特性卡片 ---- */
.feature-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}
.feature-card {
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-lg);
  padding: 32px 28px;
  transition: all var(--transition);
  position: relative;
  overflow: hidden;
}
.feature-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 3px;
  background: linear-gradient(90deg, var(--brand-primary), var(--brand-accent));
  opacity: 0;
  transition: opacity var(--transition);
}
.feature-card:hover { border-color: var(--border-color); transform: translateY(-4px); box-shadow: var(--shadow-card); }
.feature-card:hover::before { opacity: 1; }
.feature-icon {
  width: 56px;
  height: 56px;
  background: rgba(255,107,26,0.12);
  border-radius: 16px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 26px;
  margin-bottom: 20px;
  border: 1px solid rgba(255,107,26,0.2);
}
.feature-title { font-size: 18px; font-weight: 700; color: #fff; margin-bottom: 10px; }
.feature-desc { font-size: 14px; color: var(--text-muted); line-height: 1.8; }

/* ---- AI赋能区块 ---- */
.ai-section { background: linear-gradient(135deg, var(--bg-section) 0%, #0a1628 100%); }
.ai-layout {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 60px;
  align-items: center;
}
.ai-img-wrap {
  border-radius: var(--radius-lg);
  overflow: hidden;
  box-shadow: var(--shadow-glow);
  border: 1px solid var(--border-color);
}
.ai-img-wrap img { width: 100%; display: block; }
.ai-features { display: flex; flex-direction: column; gap: 24px; }
.ai-item { display: flex; gap: 16px; align-items: flex-start; }
.ai-item-icon {
  width: 44px;
  height: 44px;
  background: rgba(255,107,26,0.1);
  border: 1px solid rgba(255,107,26,0.25);
  border-radius: 12px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 20px;
  flex-shrink: 0;
}
.ai-item-body h4 { font-size: 16px; font-weight: 700; color: #fff; margin-bottom: 6px; }
.ai-item-body p { font-size: 14px; color: var(--text-muted); line-height: 1.7; }

/* ---- 社区功能 ---- */
.community-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 20px;
}
.community-card {
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  padding: 28px 24px;
  transition: all var(--transition);
}
.community-card:hover { border-color: var(--border-color); box-shadow: var(--shadow-card); }
.community-icon { font-size: 32px; margin-bottom: 14px; }
.community-title { font-size: 17px; font-weight: 700; color: #fff; margin-bottom: 8px; }
.community-desc { font-size: 13px; color: var(--text-muted); line-height: 1.7; margin-bottom: 14px; }
.community-stats { display: flex; gap: 16px; }
.cstat strong { font-size: 18px; font-weight: 800; color: var(--brand-primary); display: block; }
.cstat span { font-size: 11px; color: var(--text-muted); }

/* ---- 专家团队 ---- */
.expert-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 24px;
}
.expert-card {
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  padding: 28px 20px;
  text-align: center;
  transition: all var(--transition);
}
.expert-card:hover { border-color: var(--border-color); transform: translateY(-4px); }
.expert-avatar {
  width: 80px;
  height: 80px;
  border-radius: 50%;
  overflow: hidden;
  margin: 0 auto 14px;
  border: 3px solid var(--brand-primary);
  box-shadow: 0 0 20px rgba(255,107,26,0.3);
}
.expert-avatar img { width: 100%; height: 100%; object-fit: cover; }
.expert-name { font-size: 17px; font-weight: 700; color: #fff; margin-bottom: 4px; }
.expert-role { font-size: 12px; color: var(--brand-primary); font-weight: 600; margin-bottom: 10px; }
.expert-bio { font-size: 13px; color: var(--text-muted); line-height: 1.6; margin-bottom: 14px; }
.expert-tags { display: flex; gap: 6px; flex-wrap: wrap; justify-content: center; margin-bottom: 14px; }
.etag { font-size: 11px; background: var(--bg-card2); color: var(--text-muted); padding: 3px 8px; border-radius: 4px; }
.expert-btns { display: flex; gap: 8px; justify-content: center; }
.btn-sm {
  font-size: 12px;
  padding: 6px 12px;
  border-radius: 6px;
  font-weight: 600;
  transition: all var(--transition);
  cursor: pointer;
  border: none;
}
.btn-sm-primary { background: var(--brand-primary); color: #fff; }
.btn-sm-outline { background: transparent; color: var(--text-muted); border: 1px solid var(--border-subtle); }
.btn-sm-primary:hover { background: var(--brand-accent); }
.btn-sm-outline:hover { border-color: var(--brand-primary); color: var(--brand-primary); }

/* ---- 合作品牌 ---- */
.partner-grid {
  display: grid;
  grid-template-columns: repeat(6, 1fr);
  gap: 16px;
}
.partner-item {
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-sm);
  padding: 20px 16px;
  text-align: center;
  font-size: 13px;
  font-weight: 600;
  color: var(--text-muted);
  transition: all var(--transition);
}
.partner-item:hover { border-color: var(--border-color); color: var(--brand-primary); }
.partner-logo { font-size: 24px; margin-bottom: 8px; }

/* ---- How-To 步骤 ---- */
.howto-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 24px;
  position: relative;
}
.howto-grid::before {
  content: '';
  position: absolute;
  top: 28px;
  left: 12%;
  right: 12%;
  height: 2px;
  background: linear-gradient(90deg, var(--brand-primary), var(--brand-accent));
  opacity: 0.4;
}
.howto-step { text-align: center; position: relative; }
.step-circle {
  width: 56px;
  height: 56px;
  background: var(--brand-primary);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 22px;
  font-weight: 900;
  color: #fff;
  margin: 0 auto 18px;
  box-shadow: 0 4px 16px rgba(255,107,26,0.4);
  position: relative;
  z-index: 1;
}
.step-title { font-size: 16px; font-weight: 700; color: #fff; margin-bottom: 8px; }
.step-desc { font-size: 13px; color: var(--text-muted); line-height: 1.7; }

/* ---- FAQ ---- */
.faq-list { max-width: 800px; margin: 0 auto; display: flex; flex-direction: column; gap: 12px; }
.faq-item {
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  overflow: hidden;
  transition: border-color var(--transition);
}
.faq-item.open { border-color: var(--border-color); }
.faq-q {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 18px 22px;
  cursor: pointer;
  font-size: 15px;
  font-weight: 600;
  color: var(--text-main);
  user-select: none;
}
.faq-q:hover { color: var(--brand-primary); }
.faq-icon {
  font-size: 20px;
  color: var(--brand-primary);
  transition: transform var(--transition);
  flex-shrink: 0;
}
.faq-item.open .faq-icon { transform: rotate(45deg); }
.faq-a {
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.35s ease, padding 0.35s ease;
  font-size: 14px;
  color: var(--text-muted);
  line-height: 1.8;
  padding: 0 22px;
}
.faq-item.open .faq-a { max-height: 300px; padding: 0 22px 18px; }

/* ---- 用户评价 ---- */
.review-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 20px;
}
.review-card {
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  padding: 24px 20px;
  transition: all var(--transition);
}
.review-card:hover { border-color: var(--border-color); }
.review-stars { color: #ffd700; font-size: 14px; margin-bottom: 10px; letter-spacing: 2px; }
.review-text { font-size: 14px; color: var(--text-light); line-height: 1.7; margin-bottom: 14px; font-style: italic; }
.review-user { display: flex; align-items: center; gap: 10px; }
.review-avatar {
  width: 36px;
  height: 36px;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--brand-primary), var(--brand-secondary));
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 14px;
  font-weight: 700;
  color: #fff;
  flex-shrink: 0;
}
.review-name { font-size: 13px; font-weight: 600; color: var(--text-main); }
.review-date { font-size: 11px; color: var(--text-muted); }

/* ---- 联系我们 ---- */
.contact-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 40px;
  align-items: start;
}
.contact-info h3 { font-size: 22px; font-weight: 800; color: #fff; margin-bottom: 20px; }
.contact-item {
  display: flex;
  align-items: flex-start;
  gap: 14px;
  margin-bottom: 18px;
}
.contact-icon {
  width: 40px;
  height: 40px;
  background: rgba(255,107,26,0.1);
  border-radius: 10px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 18px;
  flex-shrink: 0;
}
.contact-label { font-size: 12px; color: var(--text-muted); margin-bottom: 3px; }
.contact-value { font-size: 15px; color: var(--text-main); font-weight: 500; }
.qr-row { display: flex; gap: 24px; margin-top: 24px; }
.qr-item { text-align: center; }
.qr-item img { width: 100px; height: 100px; border-radius: 8px; border: 2px solid var(--border-color); margin-bottom: 6px; }
.qr-item span { font-size: 12px; color: var(--text-muted); }

/* ---- 社交分享 ---- */
.share-bar {
  display: flex;
  align-items: center;
  gap: 10px;
  flex-wrap: wrap;
  margin-top: 20px;
}
.share-label { font-size: 13px; color: var(--text-muted); }
.share-btn {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  font-size: 12px;
  font-weight: 600;
  padding: 7px 14px;
  border-radius: 6px;
  border: none;
  cursor: pointer;
  transition: all var(--transition);
}
.share-weibo { background: #e6162d; color: #fff; }
.share-wechat { background: #07c160; 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(-1px); }

/* ---- 底部 ---- */
.site-footer {
  background: var(--bg-card);
  border-top: 1px solid var(--border-color);
  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-brand .footer-logo img { width: 36px; height: 36px; border-radius: 8px; }
.footer-brand .footer-logo span { font-size: 18px; font-weight: 800; color: #fff; }
.footer-brand .footer-logo span em { color: var(--brand-primary); font-style: normal; }
.footer-intro { font-size: 13px; color: var(--text-muted); line-height: 1.8; margin-bottom: 20px; }
.footer-col h4 { font-size: 14px; font-weight: 700; color: #fff; margin-bottom: 16px; padding-bottom: 8px; border-bottom: 1px solid var(--border-subtle); }
.footer-col ul { list-style: none; display: flex; flex-direction: column; gap: 8px; }
.footer-col ul li a { font-size: 13px; color: var(--text-muted); transition: color var(--transition); }
.footer-col ul li a:hover { color: var(--brand-primary); }
.footer-bottom {
  border-top: 1px solid var(--border-subtle);
  padding: 20px 0;
  display: flex;
  align-items: center;
  justify-content: space-between;
  font-size: 13px;
  color: var(--text-muted);
}
.footer-bottom a { color: var(--text-muted); }
.footer-bottom a:hover { color: var(--brand-primary); }
.update-time { font-size: 12px; color: var(--text-muted); }

/* ---- 回到顶部 ---- */
.back-top {
  position: fixed;
  bottom: 32px;
  right: 32px;
  width: 46px;
  height: 46px;
  background: var(--brand-primary);
  color: #fff;
  border: none;
  border-radius: 50%;
  font-size: 20px;
  cursor: pointer;
  display: none;
  align-items: center;
  justify-content: center;
  box-shadow: 0 4px 16px rgba(255,107,26,0.5);
  transition: all var(--transition);
  z-index: 999;
}
.back-top.show { display: flex; }
.back-top:hover { background: var(--brand-accent); transform: translateY(-3px); }

/* ---- 内页Banner ---- */
.inner-banner {
  background: linear-gradient(135deg, var(--bg-card2) 0%, var(--bg-section) 100%);
  border-bottom: 1px solid var(--border-color);
  padding: 48px 0 40px;
}
.breadcrumb {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 13px;
  color: var(--text-muted);
  margin-bottom: 16px;
}
.breadcrumb a { color: var(--text-muted); }
.breadcrumb a:hover { color: var(--brand-primary); }
.breadcrumb .sep { color: var(--border-color); }
.inner-title { font-size: 32px; font-weight: 800; color: #fff; margin-bottom: 8px; }
.inner-desc { font-size: 15px; color: var(--text-muted); max-width: 600px; }

/* ---- 分页 ---- */
.pagination {
  display: flex;
  justify-content: center;
  gap: 8px;
  margin-top: 40px;
}
.page-btn {
  width: 36px;
  height: 36px;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: 8px;
  font-size: 14px;
  font-weight: 600;
  background: var(--bg-card);
  color: var(--text-muted);
  border: 1px solid var(--border-subtle);
  cursor: pointer;
  transition: all var(--transition);
  text-decoration: none;
}
.page-btn:hover, .page-btn.active { background: var(--brand-primary); color: #fff; border-color: var(--brand-primary); }

/* ---- 分类Tab ---- */
.cat-tabs {
  display: flex;
  gap: 8px;
  flex-wrap: wrap;
  margin-bottom: 32px;
}
.cat-tab {
  padding: 8px 18px;
  border-radius: 20px;
  font-size: 13px;
  font-weight: 600;
  background: var(--bg-card);
  color: var(--text-muted);
  border: 1px solid var(--border-subtle);
  cursor: pointer;
  transition: all var(--transition);
}
.cat-tab:hover, .cat-tab.active {
  background: var(--brand-primary);
  color: #fff;
  border-color: var(--brand-primary);
}

/* ---- 响应式 ---- */
@media (max-width: 1100px) {
  .video-grid { grid-template-columns: repeat(3, 1fr); }
  .expert-grid { grid-template-columns: repeat(2, 1fr); }
  .partner-grid { grid-template-columns: repeat(4, 1fr); }
  .footer-grid { grid-template-columns: 1fr 1fr; }
}
@media (max-width: 768px) {
  .main-nav, .header-search { display: none; }
  .mobile-toggle { display: block; }
  .hero-content { margin-left: 0; padding: 40px 20px; }
  .hero-h1 { font-size: 32px; }
  .stats-grid { grid-template-columns: repeat(2, 1fr); }
  .video-grid, .video-grid-3 { grid-template-columns: repeat(2, 1fr); }
  .feature-grid { grid-template-columns: 1fr; }
  .ai-layout { grid-template-columns: 1fr; }
  .community-grid { grid-template-columns: repeat(2, 1fr); }
  .expert-grid { grid-template-columns: repeat(2, 1fr); }
  .howto-grid { grid-template-columns: repeat(2, 1fr); }
  .howto-grid::before { display: none; }
  .review-grid { grid-template-columns: repeat(2, 1fr); }
  .contact-grid { grid-template-columns: 1fr; }
  .partner-grid { grid-template-columns: repeat(3, 1fr); }
  .footer-grid { grid-template-columns: 1fr; }
  .footer-bottom { flex-direction: column; gap: 8px; text-align: center; }
  .section { padding: 52px 0; }
}
@media (max-width: 480px) {
  .video-grid, .video-grid-3 { grid-template-columns: 1fr; }
  .community-grid { grid-template-columns: 1fr; }
  .expert-grid { grid-template-columns: 1fr; }
  .review-grid { grid-template-columns: 1fr; }
  .howto-grid { grid-template-columns: 1fr; }
  .stats-grid { grid-template-columns: repeat(2, 1fr); }
}