/* =============================================
   溏心 - 主样式文件
   品牌色：玫瑰粉 #FF6B8A / 珊瑚红 #FF4466 / 深紫 #1a1a2e
   ============================================= */

/* ---------- CSS变量 ---------- */
:root {
  --primary: #FF4466;
  --primary-light: #FF6B8A;
  --primary-dark: #E0003A;
  --secondary: #7B2FBE;
  --accent: #FFB347;
  --dark: #1a1a2e;
  --dark2: #16213e;
  --dark3: #0f3460;
  --text: #333344;
  --text-light: #666680;
  --text-white: #f8f8ff;
  --bg: #fafafa;
  --bg2: #f4f4f8;
  --border: #e8e8f0;
  --shadow: 0 4px 20px rgba(255,68,102,0.12);
  --shadow-lg: 0 8px 40px rgba(255,68,102,0.18);
  --radius: 12px;
  --radius-lg: 20px;
  --transition: all 0.3s cubic-bezier(0.4,0,0.2,1);
}

/* ---------- 全局重置 ---------- */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; font-size: 16px; }
body {
  font-family: 'PingFang SC', 'Hiragino Sans GB', 'Microsoft YaHei', '微软雅黑', sans-serif;
  color: var(--text);
  background: var(--bg);
  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; outline: none; background: none; font-family: inherit; }
input, textarea, select { font-family: inherit; outline: none; }

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

/* ---------- 顶部公告栏 ---------- */
.3u8nejp {
  background: linear-gradient(90deg, var(--dark) 0%, var(--dark3) 100%);
  color: rgba(255,255,255,0.85);
  font-size: 13px;
  padding: 7px 0;
  text-align: center;
  position: relative;
  overflow: hidden;
}
.3u8nejp .0zxc0 { display: inline-block; white-space: nowrap; animation: marquee 30s linear infinite; }
@keyframes marquee { 0%{transform:translateX(100vw)} 100%{transform:translateX(-100%)} }
.3u8nejp a { color: var(--accent); margin: 0 8px; }

/* ---------- 头部导航 ---------- */
.site-header {
  background: #fff;
  box-shadow: 0 2px 16px rgba(0,0,0,0.08);
  position: sticky;
  top: 0;
  z-index: 1000;
}
.header-inner {
  max-width: 1280px;
  margin: 0 auto;
  padding: 0 24px;
  display: flex;
  align-items: center;
  height: 68px;
  gap: 16px;
}
.site-logo {
  display: flex;
  align-items: center;
  gap: 10px;
  flex-shrink: 0;
}
.site-logo img.logo-img {
  height: 42px;
  width: auto;
}
.site-logo .logo-text {
  font-size: 20px;
  font-weight: 800;
  background: linear-gradient(135deg, var(--primary) 0%, var(--secondary) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  letter-spacing: 1px;
}
.site-nav { display: flex; align-items: center; gap: 2px; flex: 1; flex-wrap: wrap; }
.site-nav a {
  padding: 7px 10px;
  border-radius: 8px;
  font-size: 14px;
  font-weight: 500;
  color: var(--text);
  white-space: nowrap;
}
.site-nav a:hover, .site-nav a.active {
  color: var(--primary);
  background: rgba(255,68,102,0.08);
}
.header-actions { display: flex; align-items: center; gap: 8px; flex-shrink: 0; }
.btn-login {
  padding: 8px 16px;
  border-radius: 8px;
  font-size: 14px;
  font-weight: 500;
  color: var(--primary);
  border: 1.5px solid var(--primary);
  transition: var(--transition);
}
.btn-login:hover { background: var(--primary); color: #fff; }
.btn-join {
  padding: 8px 16px;
  border-radius: 8px;
  font-size: 14px;
  font-weight: 600;
  background: linear-gradient(135deg, var(--primary) 0%, var(--secondary) 100%);
  color: #fff;
  transition: var(--transition);
}
.btn-join:hover { opacity: 0.9; transform: translateY(-1px); }
.mobile-menu-btn {
  display: none;
  flex-direction: column;
  gap: 5px;
  padding: 8px;
  cursor: pointer;
}
.mobile-menu-btn span {
  display: block;
  width: 22px;
  height: 2px;
  background: var(--text);
  border-radius: 2px;
  transition: var(--transition);
}

/* ---------- 搜索栏 ---------- */
.search-bar-wrap {
  background: var(--bg2);
  border-bottom: 1px solid var(--border);
  padding: 10px 0;
}
.search-bar-inner {
  max-width: 1280px;
  margin: 0 auto;
  padding: 0 24px;
  display: flex;
  align-items: center;
  gap: 16px;
  flex-wrap: wrap;
}
.search-form {
  display: flex;
  align-items: center;
  background: #fff;
  border: 1.5px solid var(--border);
  border-radius: 24px;
  overflow: hidden;
  flex: 1;
  min-width: 200px;
  max-width: 500px;
  transition: border-color 0.2s;
}
.search-form:focus-within { border-color: var(--primary); }
.search-form input {
  flex: 1;
  padding: 9px 16px;
  border: none;
  background: transparent;
  font-size: 14px;
  color: var(--text);
}
.search-btn {
  padding: 9px 20px;
  background: var(--primary);
  color: #fff;
  font-size: 14px;
  font-weight: 600;
  border-radius: 0 24px 24px 0;
  white-space: nowrap;
  transition: var(--transition);
}
.search-btn:hover { background: var(--primary-dark); }
.search-hot-tags { display: flex; align-items: center; gap: 8px; flex-wrap: wrap; font-size: 13px; color: var(--text-light); }
.hot-tag {
  padding: 4px 10px;
  background: rgba(255,68,102,0.08);
  color: var(--primary);
  border-radius: 12px;
  font-size: 12px;
  cursor: pointer;
  transition: var(--transition);
}
.hot-tag:hover { background: var(--primary); color: #fff; }

/* ---------- 移动端导航 ---------- */
.mobile-nav {
  position: fixed;
  inset: 0;
  background: rgba(0,0,0,0.5);
  z-index: 2000;
  display: none;
}
.mobile-nav.open { display: block; }
.mobile-nav-inner {
  position: absolute;
  right: 0;
  top: 0;
  bottom: 0;
  width: 260px;
  background: #fff;
  padding: 24px;
  display: flex;
  flex-direction: column;
  gap: 4px;
  overflow-y: auto;
}
.mobile-nav-inner a {
  padding: 12px 16px;
  border-radius: 8px;
  font-size: 15px;
  font-weight: 500;
  color: var(--text);
}
.mobile-nav-inner a:hover { background: rgba(255,68,102,0.08); color: var(--primary); }
.mobile-close {
  align-self: flex-end;
  font-size: 28px;
  cursor: pointer;
  color: var(--text-light);
  line-height: 1;
  margin-bottom: 16px;
}

/* ---------- 面包屑 ---------- */
.breadcrumb {
  max-width: 1280px;
  margin: 0 auto;
  padding: 12px 24px;
  font-size: 13px;
  color: var(--text-light);
  display: flex;
  align-items: center;
  gap: 6px;
}
.breadcrumb a { color: var(--primary); }
.breadcrumb a:hover { text-decoration: underline; }
.breadcrumb .sep { color: #ccc; }
.breadcrumb .current { color: var(--text); }

/* ---------- 页面Hero（内页标题区）---------- */
.page-hero {
  background: linear-gradient(135deg, var(--dark) 0%, var(--dark3) 100%);
  padding: 48px 0;
  margin-bottom: 0;
}
.page-hero .container { max-width: 1280px; margin: 0 auto; padding: 0 24px; }
.page-hero h1 {
  font-size: clamp(24px, 4vw, 36px);
  font-weight: 800;
  color: #fff;
  margin-bottom: 12px;
}
.page-hero p {
  font-size: 16px;
  color: rgba(255,255,255,0.7);
  max-width: 600px;
}

/* ---------- Hero Banner ---------- */
.hero-banner {
  background: linear-gradient(135deg, var(--dark) 0%, var(--dark3) 60%, var(--secondary) 100%);
  padding: 80px 24px 64px;
  text-align: center;
  position: relative;
  overflow: hidden;
}
.hero-banner::before {
  content: '';
  position: absolute;
  inset: 0;
  background: radial-gradient(ellipse at 30% 50%, rgba(255,68,102,0.15) 0%, transparent 60%),
              radial-gradient(ellipse at 70% 50%, rgba(123,47,190,0.15) 0%, transparent 60%);
}
.hero-content { position: relative; max-width: 800px; margin: 0 auto; }
.msifgb0s {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  background: rgba(255,68,102,0.15);
  border: 1px solid rgba(255,68,102,0.3);
  border-radius: 24px;
  padding: 6px 16px;
  font-size: 13px;
  color: var(--primary-light);
  margin-bottom: 24px;
}
.msifgb0s .dot {
  width: 8px;
  height: 8px;
  background: var(--primary);
  border-radius: 50%;
  animation: pulse 2s infinite;
}
@keyframes pulse { 0%,100%{opacity:1;transform:scale(1)} 50%{opacity:0.5;transform:scale(1.3)} }
.hero-content h1 {
  font-size: clamp(28px, 5vw, 52px);
  font-weight: 900;
  color: #fff;
  line-height: 1.2;
  margin-bottom: 20px;
}
.hero-content h1 .brand { color: var(--primary-light); }
.hero-content > p {
  font-size: clamp(14px, 2vw, 17px);
  color: rgba(255,255,255,0.75);
  max-width: 640px;
  margin: 0 auto 32px;
}
.hero-actions { display: flex; justify-content: center; gap: 16px; flex-wrap: wrap; margin-bottom: 40px; }
.btn-primary {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 14px 28px;
  background: linear-gradient(135deg, var(--primary) 0%, var(--primary-dark) 100%);
  color: #fff;
  border-radius: 32px;
  font-size: 16px;
  font-weight: 700;
  box-shadow: 0 4px 20px rgba(255,68,102,0.4);
  transition: var(--transition);
}
.btn-primary:hover { transform: translateY(-2px); box-shadow: 0 8px 32px rgba(255,68,102,0.5); }
.btn-outline {
  display: inline-flex;
  align-items: center;
  padding: 14px 28px;
  border: 2px solid rgba(255,255,255,0.4);
  color: rgba(255,255,255,0.9);
  border-radius: 32px;
  font-size: 16px;
  font-weight: 600;
  transition: var(--transition);
}
.btn-outline:hover { border-color: #fff; color: #fff; background: rgba(255,255,255,0.1); }
.hero-stats { display: flex; justify-content: center; gap: 40px; flex-wrap: wrap; }
.hero-stat { text-align: center; }
.hero-stat .num { display: block; font-size: 28px; font-weight: 800; color: #fff; }
.hero-stat .label { font-size: 13px; color: rgba(255,255,255,0.6); }

/* ---------- 通用Section ---------- */
.section { padding: 64px 0; }
.section-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 32px;
  flex-wrap: wrap;
  gap: 12px;
}
.section-header h2 {
  font-size: clamp(20px, 3vw, 28px);
  font-weight: 800;
  color: var(--text);
}
.view-more {
  font-size: 14px;
  color: var(--primary);
  font-weight: 600;
  white-space: nowrap;
}
.view-more:hover { text-decoration: underline; }
.section-title { text-align: center; margin-bottom: 48px; }
.section-title h2 {
  font-size: clamp(22px, 3.5vw, 32px);
  font-weight: 800;
  color: var(--text);
  margin-bottom: 12px;
}
.section-title h3 {
  font-size: clamp(18px, 2.5vw, 24px);
  font-weight: 700;
  color: var(--text);
  margin-bottom: 10px;
}
.section-title p { font-size: 15px; color: var(--text-light); max-width: 600px; margin: 0 auto; }

/* ---------- 分类标签 ---------- */
.category-tabs {
  display: flex;
  gap: 8px;
  flex-wrap: wrap;
  margin-bottom: 28px;
}
.cat-tab {
  padding: 7px 16px;
  border-radius: 20px;
  font-size: 13px;
  font-weight: 500;
  cursor: pointer;
  border: 1.5px solid var(--border);
  color: var(--text-light);
  transition: var(--transition);
  background: #fff;
}
.cat-tab:hover, .cat-tab.active {
  border-color: var(--primary);
  color: var(--primary);
  background: rgba(255,68,102,0.06);
}

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

/* ---------- 视频卡片 ---------- */
.video-card {
  background: #fff;
  border-radius: var(--radius);
  overflow: hidden;
  box-shadow: 0 2px 12px rgba(0,0,0,0.06);
  transition: var(--transition);
  cursor: pointer;
}
.video-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-lg);
}
.video-thumb {
  position: relative;
  overflow: hidden;
  aspect-ratio: 16/9;
  background: var(--dark);
}
.video-thumb img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform 0.4s ease;
}
.video-card:hover .video-thumb img { transform: scale(1.06); }

/* ---- 播放按钮 hover 效果（核心SEO视频属性） ---- */
.play-overlay {
  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-overlay {
  background: rgba(0,0,0,0.35);
}
.play-btn {
  width: 52px;
  height: 52px;
  background: rgba(255,68,102,0.9);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  opacity: 0;
  transform: scale(0.8);
  transition: opacity 0.3s ease, transform 0.3s ease;
  box-shadow: 0 4px 20px rgba(255,68,102,0.5);
}
.video-card:hover .play-btn {
  opacity: 1;
  transform: scale(1);
}
.play-btn svg {
  width: 22px;
  height: 22px;
  fill: #fff;
  margin-left: 3px;
}
.video-duration {
  position: absolute;
  bottom: 8px;
  right: 8px;
  background: rgba(0,0,0,0.75);
  color: #fff;
  font-size: 11px;
  padding: 2px 7px;
  border-radius: 4px;
}
.video-tag {
  position: absolute;
  top: 8px;
  left: 8px;
  background: var(--primary);
  color: #fff;
  font-size: 11px;
  padding: 2px 8px;
  border-radius: 4px;
  font-weight: 600;
}
.video-info { padding: 14px; }
.video-title {
  font-size: 14px;
  font-weight: 600;
  color: var(--text);
  line-height: 1.5;
  margin-bottom: 10px;
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
}
.video-meta { display: flex; align-items: center; gap: 8px; margin-bottom: 8px; }
.video-meta .author {
  display: flex;
  align-items: center;
  gap: 6px;
  font-size: 12px;
  color: var(--text-light);
}
.video-meta .author img {
  width: 22px;
  height: 22px;
  border-radius: 50%;
  object-fit: cover;
}
.video-stats { display: flex; gap: 12px; font-size: 12px; color: var(--text-light); }

/* ---------- AI赋能模块 ---------- */
.ai-section { background: linear-gradient(135deg, var(--dark) 0%, var(--dark3) 100%); }
.ai-section .section-title h2 { color: #fff; }
.ai-section .section-title p { color: rgba(255,255,255,0.6); }
.ai-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 24px; }
.ai-card {
  background: rgba(255,255,255,0.06);
  border: 1px solid rgba(255,255,255,0.1);
  border-radius: var(--radius-lg);
  padding: 32px 24px;
  text-align: center;
  transition: var(--transition);
}
.ai-card:hover { background: rgba(255,68,102,0.1); border-color: rgba(255,68,102,0.3); transform: translateY(-4px); }
.ai-icon { font-size: 40px; display: block; margin-bottom: 16px; }
.ai-card h3 { font-size: 18px; font-weight: 700; color: #fff; margin-bottom: 12px; }
.ai-card p { font-size: 14px; color: rgba(255,255,255,0.65); line-height: 1.7; }

/* ---------- 社区功能模块 ---------- */
.feature-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 20px; }
.feature-card {
  background: #fff;
  border-radius: var(--radius);
  padding: 28px 20px;
  text-align: center;
  box-shadow: 0 2px 12px rgba(0,0,0,0.06);
  transition: var(--transition);
}
.feature-card:hover { transform: translateY(-4px); box-shadow: var(--shadow); }
.feature-icon { font-size: 36px; display: block; margin-bottom: 14px; }
.feature-card h3 { font-size: 16px; font-weight: 700; color: var(--text); margin-bottom: 10px; }
.feature-card p { font-size: 13px; color: var(--text-light); line-height: 1.6; }

/* ---------- 专家卡片 ---------- */
.expert-grid { display: grid; grid-template-columns: repeat(2, 1fr); gap: 24px; }
.expert-card {
  background: #fff;
  border-radius: var(--radius-lg);
  padding: 32px;
  box-shadow: 0 2px 16px rgba(0,0,0,0.06);
  display: flex;
  flex-direction: column;
  align-items: center;
  text-align: center;
  transition: var(--transition);
}
.expert-card:hover { box-shadow: var(--shadow); transform: translateY(-4px); }
.expert-avatar {
  width: 96px;
  height: 96px;
  border-radius: 50%;
  object-fit: cover;
  border: 4px solid var(--primary-light);
  margin-bottom: 16px;
}
.expert-name { font-size: 20px; font-weight: 800; color: var(--text); margin-bottom: 6px; }
.expert-role { font-size: 14px; color: var(--primary); font-weight: 600; margin-bottom: 12px; }
.expert-desc { font-size: 13px; color: var(--text-light); line-height: 1.7; margin-bottom: 16px; }
.expert-awards { display: flex; gap: 8px; flex-wrap: wrap; justify-content: center; margin-bottom: 16px; }
.award-tag {
  padding: 4px 12px;
  background: rgba(255,68,102,0.08);
  color: var(--primary);
  border-radius: 12px;
  font-size: 12px;
  font-weight: 600;
}
.expert-actions { display: flex; gap: 10px; }
.btn-sm {
  padding: 8px 18px;
  border-radius: 20px;
  font-size: 13px;
  font-weight: 600;
  transition: var(--transition);
}
.btn-sm-primary { background: var(--primary); color: #fff; }
.btn-sm-primary:hover { background: var(--primary-dark); }
.btn-sm-outline { border: 1.5px solid var(--primary); color: var(--primary); }
.btn-sm-outline:hover { background: var(--primary); color: #fff; }

/* ---------- 合作品牌 ---------- */
.0gzhuh0v { display: flex; gap: 16px; flex-wrap: wrap; justify-content: center; }
.9fuhc5ww {
  padding: 12px 24px;
  background: #fff;
  border: 1.5px solid var(--border);
  border-radius: var(--radius);
  font-size: 14px;
  font-weight: 600;
  color: var(--text-light);
  transition: var(--transition);
}
.9fuhc5ww:hover { border-color: var(--primary); color: var(--primary); }

/* ---------- 步骤卡片 ---------- */
.howto-steps { display: grid; grid-template-columns: repeat(4, 1fr); gap: 20px; }
.step-card {
  background: #fff;
  border-radius: var(--radius);
  padding: 28px 20px;
  text-align: center;
  box-shadow: 0 2px 12px rgba(0,0,0,0.06);
  transition: var(--transition);
}
.step-card:hover { box-shadow: var(--shadow); transform: translateY(-3px); }
.step-num {
  width: 48px;
  height: 48px;
  background: linear-gradient(135deg, var(--primary) 0%, var(--secondary) 100%);
  color: #fff;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 20px;
  font-weight: 800;
  margin: 0 auto 16px;
}
.step-card h3 { font-size: 16px; font-weight: 700; color: var(--text); margin-bottom: 10px; }
.step-card p { font-size: 13px; color: var(--text-light); line-height: 1.6; }

/* ---------- 用户评价 ---------- */
.review-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 20px; }
.review-card {
  background: #fff;
  border-radius: var(--radius);
  padding: 24px;
  box-shadow: 0 2px 12px rgba(0,0,0,0.06);
  transition: var(--transition);
}
.review-card:hover { box-shadow: var(--shadow); transform: translateY(-3px); }
.review-header { display: flex; align-items: center; gap: 12px; margin-bottom: 12px; }
.review-avatar {
  width: 44px;
  height: 44px;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--primary) 0%, var(--secondary) 100%);
  color: #fff;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 18px;
  font-weight: 700;
  flex-shrink: 0;
}
.review-user-name { font-size: 15px; font-weight: 700; color: var(--text); margin-bottom: 2px; }
.review-date { font-size: 12px; color: var(--text-light); }
.review-stars { margin-bottom: 10px; }
.star { color: #FFB347; font-size: 16px; }
.review-text { font-size: 14px; color: var(--text); line-height: 1.7; margin-bottom: 12px; }
.review-tag {
  display: inline-block;
  padding: 3px 10px;
  background: rgba(255,68,102,0.08);
  color: var(--primary);
  border-radius: 10px;
  font-size: 12px;
  font-weight: 600;
}

/* ---------- FAQ ---------- */
.faq-list { max-width: 800px; margin: 0 auto; display: flex; flex-direction: column; gap: 12px; }
.faq-item {
  background: #fff;
  border-radius: var(--radius);
  border: 1.5px solid var(--border);
  overflow: hidden;
  transition: var(--transition);
}
.faq-item.open { border-color: var(--primary); }
.faq-question {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 18px 24px;
  cursor: pointer;
  font-size: 15px;
  font-weight: 600;
  color: var(--text);
  user-select: none;
}
.faq-item.open .faq-question { color: var(--primary); }
.q-icon { color: var(--primary); margin-right: 6px; font-weight: 800; }
.arrow { font-size: 12px; color: var(--text-light); transition: transform 0.3s; }
.faq-item.open .arrow { transform: rotate(180deg); }
.faq-answer { display: none; padding: 0 24px 18px; }
.faq-item.open .faq-answer { display: block; }
.faq-answer p { font-size: 14px; color: var(--text-light); line-height: 1.8; }

/* ---------- 联系信息 ---------- */
.contact-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 24px; }
.contact-card {
  background: #fff;
  border-radius: var(--radius-lg);
  padding: 32px;
  box-shadow: 0 2px 16px rgba(0,0,0,0.06);
  text-align: center;
  transition: var(--transition);
}
.contact-card:hover { box-shadow: var(--shadow); transform: translateY(-4px); }
.contact-icon { font-size: 40px; margin-bottom: 16px; }
.contact-card h3 { font-size: 18px; font-weight: 700; color: var(--text); margin-bottom: 14px; }
.contact-card p { font-size: 14px; color: var(--text-light); line-height: 1.8; margin-bottom: 6px; }
.qr-img { width: 120px; height: 120px; margin: 12px auto 0; border-radius: 8px; }

/* ---------- 页脚 ---------- */
.site-footer {
  background: linear-gradient(135deg, var(--dark) 0%, var(--dark2) 100%);
  color: rgba(255,255,255,0.7);
  padding-top: 56px;
}
.footer-grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1fr;
  gap: 40px;
  padding-bottom: 40px;
  border-bottom: 1px solid rgba(255,255,255,0.1);
}
.footer-brand .logo-wrap {
  display: flex;
  align-items: center;
  gap: 10px;
  margin-bottom: 16px;
}
.footer-brand .logo-wrap span {
  font-size: 20px;
  font-weight: 800;
  color: #fff;
}
.footer-brand p { font-size: 13px; line-height: 1.8; margin-bottom: 16px; }
.footer-qr-row { display: flex; gap: 16px; }
.footer-qr { text-align: center; }
.footer-qr img { width: 80px; height: 80px; border-radius: 8px; margin-bottom: 6px; }
.footer-qr span { font-size: 11px; color: rgba(255,255,255,0.5); }
.footer-col h4 { font-size: 15px; font-weight: 700; color: #fff; margin-bottom: 16px; }
.footer-col ul { display: flex; flex-direction: column; gap: 8px; }
.footer-col ul li a { font-size: 13px; color: rgba(255,255,255,0.55); transition: color 0.2s; }
.footer-col ul li a:hover { color: var(--primary-light); }
.footer-bottom {
  padding: 20px 0;
  font-size: 13px;
  color: rgba(255,255,255,0.35);
}
.footer-bottom a { color: rgba(255,255,255,0.4); }
.footer-bottom a:hover { color: var(--primary-light); }
.footer-bottom span { margin: 0 4px; }

/* ---------- 分享按钮 ---------- */
.share-bar { display: flex; align-items: center; gap: 10px; flex-wrap: wrap; }
.share-bar > span { font-size: 13px; color: var(--text-light); }
.share-btn {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 7px 14px;
  border-radius: 20px;
  font-size: 13px;
  font-weight: 500;
  border: 1.5px solid var(--border);
  color: var(--text-light);
  background: #fff;
  transition: var(--transition);
}
.share-btn:hover { border-color: var(--primary); color: var(--primary); }

/* ---------- 回到顶部 ---------- */
.back-to-top {
  position: fixed;
  bottom: 32px;
  right: 32px;
  width: 44px;
  height: 44px;
  background: var(--primary);
  color: #fff;
  border-radius: 50%;
  font-size: 18px;
  display: flex;
  align-items: center;
  justify-content: center;
  box-shadow: 0 4px 16px rgba(255,68,102,0.4);
  opacity: 0;
  transform: translateY(20px);
  transition: var(--transition);
  z-index: 999;
}
.back-to-top.visible { opacity: 1; transform: translateY(0); }
.back-to-top:hover { background: var(--primary-dark); transform: translateY(-2px); }

/* ---------- 响应式 ---------- */
@media (max-width: 1100px) {
  .video-grid-4 { grid-template-columns: repeat(2, 1fr); }
  .feature-grid { grid-template-columns: repeat(2, 1fr); }
  .howto-steps { grid-template-columns: repeat(2, 1fr); }
  .footer-grid { grid-template-columns: 1fr 1fr; }
}

@media (max-width: 768px) {
  .site-nav { display: none; }
  .header-actions { display: none; }
  .mobile-menu-btn { display: flex; }
  .video-grid-3 { grid-template-columns: repeat(2, 1fr); }
  .video-grid-4 { grid-template-columns: repeat(2, 1fr); }
  .ai-grid { grid-template-columns: 1fr; }
  .expert-grid { grid-template-columns: 1fr; }
  .review-grid { grid-template-columns: 1fr; }
  .contact-grid { grid-template-columns: 1fr; }
  .footer-grid { grid-template-columns: 1fr; }
  .hero-banner { padding: 56px 20px 48px; }
  .hero-stats { gap: 20px; }
  .section { padding: 40px 0; }
}

@media (max-width: 480px) {
  .video-grid-3, .video-grid-4 { grid-template-columns: 1fr; }
  .feature-grid { grid-template-columns: 1fr; }
  .howto-steps { grid-template-columns: 1fr; }
  .hero-actions { flex-direction: column; align-items: center; }
  .search-bar-inner { flex-direction: column; align-items: stretch; }
  .search-form { max-width: 100%; }
}