/* ============================================
   国产主播 影视传媒 - 原创样式表
   品牌色系：深邃靛蓝 + 活力橙 + 薄荷绿
   kwantat.cn
   ============================================ */

/* CSS变量定义 */
:root {
  --primary: #1A1F35;
  --secondary: #FF6B35;
  --accent: #00D4AA;
  --bg-dark: #0D1117;
  --bg-card: #161B2E;
  --bg-card-hover: #1E2440;
  --text-main: #E8ECF1;
  --text-sub: #8B95A5;
  --text-muted: #5A6377;
  --border-color: #2A3050;
  --gradient-primary: linear-gradient(135deg, #1A1F35 0%, #0D1117 100%);
  --gradient-accent: linear-gradient(135deg, #FF6B35 0%, #FF8F5E 100%);
  --gradient-mint: linear-gradient(135deg, #00D4AA 0%, #00F5C8 100%);
  --shadow-card: 0 8px 32px rgba(0,0,0,0.3);
  --shadow-hover: 0 12px 48px rgba(255,107,53,0.15);
  --radius-sm: 6px;
  --radius-md: 12px;
  --radius-lg: 20px;
  --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

/* 基础重置 */
*, *::before, *::after {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
  font-size: 16px;
}

body {
  font-family: "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "WenQuanYi Micro Hei", sans-serif;
  background: var(--bg-dark);
  color: var(--text-main);
  line-height: 1.7;
  overflow-x: hidden;
  -webkit-font-smoothing: antialiased;
}

a {
  color: var(--secondary);
  text-decoration: none;
  transition: var(--transition);
}

a:hover {
  color: var(--accent);
}

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

ul, ol {
  list-style: none;
}

/* ============================================
   顶部导航栏
   ============================================ */
.site-header {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  z-index: 1000;
  background: rgba(13, 17, 23, 0.92);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border-bottom: 1px solid var(--border-color);
  transition: var(--transition);
}

.site-header.scrolled {
  background: rgba(13, 17, 23, 0.98);
  box-shadow: 0 4px 20px rgba(0,0,0,0.4);
}

.header-inner {
  max-width: 1400px;
  margin: 0 auto;
  padding: 0 24px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 68px;
}

.logo-wrap {
  display: flex;
  align-items: center;
  gap: 10px;
}

.logo-wrap img {
  height: 42px;
  width: auto;
}

.logo-wrap .brand-text {
  font-size: 1.5rem;
  font-weight: 800;
  color: var(--secondary);
  letter-spacing: 1px;
}

.main-nav {
  display: flex;
  align-items: center;
  gap: 6px;
}

.main-nav a {
  color: var(--text-main);
  font-size: 0.95rem;
  padding: 8px 16px;
  border-radius: var(--radius-sm);
  transition: var(--transition);
  position: relative;
  font-weight: 500;
}

.main-nav a:hover,
.main-nav a.active {
  color: var(--secondary);
  background: rgba(255, 107, 53, 0.08);
}

.main-nav a.active::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 50%;
  transform: translateX(-50%);
  width: 20px;
  height: 2px;
  background: var(--secondary);
  border-radius: 1px;
}

/* 移动端菜单按钮 */
.menu-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  cursor: pointer;
  padding: 8px;
}

.menu-toggle span {
  width: 24px;
  height: 2px;
  background: var(--text-main);
  border-radius: 2px;
  transition: var(--transition);
}

/* ============================================
   搜索框
   ============================================ */
.search-bar-wrap {
  background: var(--primary);
  padding: 12px 0;
  border-bottom: 1px solid var(--border-color);
  margin-top: 68px;
}

.search-bar-inner {
  max-width: 680px;
  margin: 0 auto;
  padding: 0 24px;
  position: relative;
}

.search-bar-inner input {
  width: 100%;
  padding: 12px 48px 12px 20px;
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: 50px;
  color: var(--text-main);
  font-size: 0.95rem;
  outline: none;
  transition: var(--transition);
}

.search-bar-inner input::placeholder {
  color: var(--text-muted);
}

.search-bar-inner input:focus {
  border-color: var(--secondary);
  box-shadow: 0 0 0 3px rgba(255, 107, 53, 0.1);
}

.search-bar-inner .search-btn {
  position: absolute;
  right: 32px;
  top: 50%;
  transform: translateY(-50%);
  background: none;
  border: none;
  color: var(--secondary);
  font-size: 1.2rem;
  cursor: pointer;
  padding: 4px 8px;
}

/* ============================================
   Banner 大图区域
   ============================================ */
.hero-banner {
  position: relative;
  width: 100%;
  min-height: 520px;
  overflow: hidden;
  display: flex;
  align-items: center;
  justify-content: center;
}

.hero-banner .banner-bg {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
  filter: brightness(0.45);
}

.hero-banner .banner-overlay {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: linear-gradient(180deg, rgba(13,17,23,0.3) 0%, rgba(13,17,23,0.85) 100%);
}

.hero-content {
  position: relative;
  z-index: 2;
  text-align: center;
  max-width: 800px;
  padding: 60px 24px;
}

.hero-content h1 {
  font-size: 2.8rem;
  font-weight: 800;
  margin-bottom: 16px;
  line-height: 1.3;
}

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

.hero-content .hero-desc {
  font-size: 1.15rem;
  color: var(--text-sub);
  margin-bottom: 32px;
  line-height: 1.8;
}

.hero-content .hero-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  justify-content: center;
  margin-bottom: 28px;
}

.hero-content .hero-tags span {
  background: rgba(255, 107, 53, 0.12);
  color: var(--secondary);
  padding: 6px 16px;
  border-radius: 50px;
  font-size: 0.85rem;
  border: 1px solid rgba(255, 107, 53, 0.2);
}

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

.btn-primary {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 12px 32px;
  background: var(--gradient-accent);
  color: #fff;
  border: none;
  border-radius: 50px;
  font-size: 1rem;
  font-weight: 600;
  cursor: pointer;
  transition: var(--transition);
  text-decoration: none;
}

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 24px rgba(255, 107, 53, 0.35);
  color: #fff;
}

.btn-outline {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 12px 32px;
  background: transparent;
  color: var(--accent);
  border: 2px solid var(--accent);
  border-radius: 50px;
  font-size: 1rem;
  font-weight: 600;
  cursor: pointer;
  transition: var(--transition);
  text-decoration: none;
}

.btn-outline:hover {
  background: var(--accent);
  color: var(--bg-dark);
  transform: translateY(-2px);
}

/* ============================================
   通用容器
   ============================================ */
.container {
  max-width: 1400px;
  margin: 0 auto;
  padding: 0 24px;
}

/* ============================================
   区块标题
   ============================================ */
.section-block {
  padding: 64px 0;
}

.section-block:nth-child(even) {
  background: var(--primary);
}

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

.section-title h2 {
  font-size: 2rem;
  font-weight: 700;
  margin-bottom: 12px;
  position: relative;
  display: inline-block;
}

.section-title h2 .hl {
  color: var(--secondary);
}

.section-title h2::after {
  content: '';
  display: block;
  width: 48px;
  height: 3px;
  background: var(--gradient-accent);
  margin: 12px auto 0;
  border-radius: 2px;
}

.section-title p {
  color: var(--text-sub);
  font-size: 1rem;
  max-width: 600px;
  margin: 0 auto;
}

/* ============================================
   视频卡片网格
   ============================================ */
.video-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(320px, 1fr));
  gap: 24px;
}

.video-card {
  background: var(--bg-card);
  border-radius: var(--radius-md);
  overflow: hidden;
  transition: var(--transition);
  border: 1px solid var(--border-color);
  cursor: pointer;
}

.video-card:hover {
  transform: translateY(-6px);
  box-shadow: var(--shadow-hover);
  border-color: rgba(255, 107, 53, 0.3);
}

.video-card .thumb-wrap {
  position: relative;
  width: 100%;
  padding-top: 56.25%;
  overflow: hidden;
}

.video-card .thumb-wrap img {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform 0.5s ease;
}

.video-card:hover .thumb-wrap img {
  transform: scale(1.05);
}

.video-card .play-btn {
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%) scale(0.8);
  width: 60px;
  height: 60px;
  background: rgba(255, 107, 53, 0.9);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  opacity: 0;
  transition: var(--transition);
}

.video-card:hover .play-btn {
  opacity: 1;
  transform: translate(-50%, -50%) scale(1);
}

.video-card .play-btn::after {
  content: '';
  display: block;
  width: 0;
  height: 0;
  border-style: solid;
  border-width: 10px 0 10px 18px;
  border-color: transparent transparent transparent #fff;
  margin-left: 3px;
}

.video-card .duration-tag {
  position: absolute;
  bottom: 8px;
  right: 8px;
  background: rgba(0,0,0,0.75);
  color: #fff;
  padding: 2px 8px;
  border-radius: 4px;
  font-size: 0.8rem;
  font-weight: 500;
}

.video-card .card-body {
  padding: 16px;
}

.video-card .card-body h3 {
  font-size: 1.05rem;
  font-weight: 600;
  margin-bottom: 8px;
  line-height: 1.4;
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

.video-card .card-meta {
  display: flex;
  align-items: center;
  gap: 16px;
  color: var(--text-muted);
  font-size: 0.85rem;
}

.video-card .card-meta span {
  display: flex;
  align-items: center;
  gap: 4px;
}

.video-card .card-tags {
  display: flex;
  gap: 6px;
  margin-top: 10px;
  flex-wrap: wrap;
}

.video-card .card-tags span {
  background: rgba(0, 212, 170, 0.1);
  color: var(--accent);
  padding: 2px 10px;
  border-radius: 50px;
  font-size: 0.75rem;
}

/* ============================================
   栏目分类导航条
   ============================================ */
.category-tabs {
  display: flex;
  gap: 8px;
  justify-content: center;
  flex-wrap: wrap;
  margin-bottom: 36px;
}

.category-tabs a {
  padding: 8px 20px;
  background: var(--bg-card);
  color: var(--text-sub);
  border-radius: 50px;
  font-size: 0.9rem;
  border: 1px solid var(--border-color);
  transition: var(--transition);
}

.category-tabs a:hover,
.category-tabs a.active {
  background: var(--secondary);
  color: #fff;
  border-color: var(--secondary);
}

/* ============================================
   数据统计条
   ============================================ */
.stats-bar {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 24px;
  padding: 48px 0;
}

.stat-item {
  text-align: center;
  padding: 24px;
  background: var(--bg-card);
  border-radius: var(--radius-md);
  border: 1px solid var(--border-color);
}

.stat-item .stat-num {
  font-size: 2.4rem;
  font-weight: 800;
  color: var(--secondary);
  line-height: 1.2;
}

.stat-item .stat-label {
  color: var(--text-sub);
  font-size: 0.9rem;
  margin-top: 6px;
}

/* ============================================
   专家展示卡片
   ============================================ */
.expert-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 24px;
}

.expert-card {
  background: var(--bg-card);
  border-radius: var(--radius-md);
  padding: 28px;
  text-align: center;
  border: 1px solid var(--border-color);
  transition: var(--transition);
}

.expert-card:hover {
  border-color: var(--accent);
  box-shadow: 0 8px 32px rgba(0, 212, 170, 0.1);
}

.expert-card .avatar {
  width: 100px;
  height: 100px;
  border-radius: 50%;
  object-fit: cover;
  margin: 0 auto 16px;
  border: 3px solid var(--accent);
}

.expert-card h4 {
  font-size: 1.1rem;
  font-weight: 600;
  margin-bottom: 4px;
}

.expert-card .role {
  color: var(--secondary);
  font-size: 0.85rem;
  margin-bottom: 12px;
}

.expert-card .bio {
  color: var(--text-sub);
  font-size: 0.88rem;
  line-height: 1.6;
  margin-bottom: 16px;
}

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

.expert-card .expert-btns a {
  padding: 6px 16px;
  border-radius: 50px;
  font-size: 0.82rem;
  font-weight: 500;
}

.expert-card .expert-btns .btn-sm-primary {
  background: var(--secondary);
  color: #fff;
}

.expert-card .expert-btns .btn-sm-outline {
  border: 1px solid var(--accent);
  color: var(--accent);
}

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

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

.faq-item .faq-q {
  padding: 18px 24px;
  font-weight: 600;
  font-size: 1rem;
  cursor: pointer;
  display: flex;
  justify-content: space-between;
  align-items: center;
  transition: var(--transition);
}

.faq-item .faq-q:hover {
  color: var(--secondary);
}

.faq-item .faq-q .arrow {
  font-size: 1.2rem;
  transition: transform 0.3s ease;
  color: var(--secondary);
}

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

.faq-item .faq-a {
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.4s ease;
}

.faq-item.open .faq-a {
  max-height: 400px;
}

.faq-item .faq-a-inner {
  padding: 0 24px 18px;
  color: var(--text-sub);
  font-size: 0.95rem;
  line-height: 1.8;
}

/* ============================================
   用户评论
   ============================================ */
.review-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
  gap: 24px;
}

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

.review-card .review-header {
  display: flex;
  align-items: center;
  gap: 12px;
  margin-bottom: 14px;
}

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

.review-card .review-name {
  font-weight: 600;
  font-size: 0.95rem;
}

.review-card .review-date {
  color: var(--text-muted);
  font-size: 0.8rem;
}

.review-card .stars {
  color: #FFB800;
  font-size: 0.9rem;
  letter-spacing: 2px;
  margin-bottom: 10px;
}

.review-card .review-text {
  color: var(--text-sub);
  font-size: 0.92rem;
  line-height: 1.7;
}

/* ============================================
   合作品牌Logo墙
   ============================================ */
.partner-wall {
  display: flex;
  flex-wrap: wrap;
  gap: 24px;
  justify-content: center;
  align-items: center;
}

.partner-wall .partner-item {
  width: 160px;
  height: 80px;
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 16px;
  transition: var(--transition);
  color: var(--text-sub);
  font-weight: 600;
  font-size: 0.9rem;
}

.partner-wall .partner-item:hover {
  border-color: var(--secondary);
  background: var(--bg-card-hover);
}

/* ============================================
   联系信息
   ============================================ */
.contact-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 24px;
}

.contact-card {
  background: var(--bg-card);
  border-radius: var(--radius-md);
  padding: 28px;
  border: 1px solid var(--border-color);
  text-align: center;
}

.contact-card .contact-icon {
  width: 56px;
  height: 56px;
  background: rgba(255, 107, 53, 0.1);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  margin: 0 auto 16px;
  font-size: 1.5rem;
  color: var(--secondary);
}

.contact-card h4 {
  font-size: 1rem;
  margin-bottom: 8px;
}

.contact-card p {
  color: var(--text-sub);
  font-size: 0.9rem;
}

/* ============================================
   社交分享按钮
   ============================================ */
.share-btns {
  display: flex;
  gap: 12px;
  justify-content: center;
  flex-wrap: wrap;
}

.share-btns a {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 8px 20px;
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: 50px;
  color: var(--text-main);
  font-size: 0.88rem;
  transition: var(--transition);
}

.share-btns a:hover {
  border-color: var(--secondary);
  color: var(--secondary);
  background: rgba(255, 107, 53, 0.08);
}

/* ============================================
   页脚
   ============================================ */
.site-footer {
  background: var(--primary);
  border-top: 1px solid var(--border-color);
  padding: 48px 0 24px;
}

.footer-grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1fr;
  gap: 40px;
  margin-bottom: 36px;
}

.footer-brand .footer-logo {
  height: 40px;
  margin-bottom: 14px;
}

.footer-brand p {
  color: var(--text-sub);
  font-size: 0.9rem;
  line-height: 1.7;
  margin-bottom: 16px;
}

.footer-col h5 {
  font-size: 1rem;
  font-weight: 600;
  margin-bottom: 16px;
  color: var(--text-main);
}

.footer-col a {
  display: block;
  color: var(--text-sub);
  font-size: 0.88rem;
  padding: 4px 0;
  transition: var(--transition);
}

.footer-col a:hover {
  color: var(--secondary);
  padding-left: 4px;
}

.footer-qr {
  display: flex;
  gap: 20px;
  margin-top: 12px;
}

.footer-qr .qr-item {
  text-align: center;
}

.footer-qr .qr-item img {
  width: 100px;
  height: 100px;
  border-radius: var(--radius-sm);
  margin-bottom: 6px;
}

.footer-qr .qr-item span {
  font-size: 0.78rem;
  color: var(--text-muted);
}

.footer-bottom {
  border-top: 1px solid var(--border-color);
  padding-top: 20px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 12px;
}

.footer-bottom p {
  color: var(--text-muted);
  font-size: 0.82rem;
}

/* ============================================
   面包屑导航
   ============================================ */
.breadcrumb {
  padding: 16px 0;
  margin-top: 68px;
}

.breadcrumb-list {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 0.88rem;
  color: var(--text-muted);
}

.breadcrumb-list a {
  color: var(--text-sub);
}

.breadcrumb-list a:hover {
  color: var(--secondary);
}

.breadcrumb-list .sep {
  color: var(--text-muted);
}

.breadcrumb-list .current {
  color: var(--secondary);
}

/* ============================================
   内页通用头部
   ============================================ */
.page-hero {
  position: relative;
  min-height: 280px;
  display: flex;
  align-items: center;
  overflow: hidden;
  margin-top: 68px;
}

.page-hero .page-hero-bg {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
  filter: brightness(0.35);
}

.page-hero .page-hero-overlay {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: linear-gradient(180deg, rgba(13,17,23,0.2) 0%, rgba(13,17,23,0.9) 100%);
}

.page-hero .page-hero-content {
  position: relative;
  z-index: 2;
  padding: 48px 24px;
  max-width: 1400px;
  margin: 0 auto;
  width: 100%;
}

.page-hero h1 {
  font-size: 2.2rem;
  font-weight: 700;
  margin-bottom: 10px;
}

.page-hero .page-desc {
  color: var(--text-sub);
  font-size: 1.05rem;
  max-width: 600px;
}

/* ============================================
   How-To 指南
   ============================================ */
.howto-steps {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(250px, 1fr));
  gap: 24px;
  counter-reset: step;
}

.howto-step {
  background: var(--bg-card);
  border-radius: var(--radius-md);
  padding: 28px;
  border: 1px solid var(--border-color);
  position: relative;
  counter-increment: step;
}

.howto-step::before {
  content: counter(step);
  position: absolute;
  top: -12px;
  left: 20px;
  width: 32px;
  height: 32px;
  background: var(--gradient-accent);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  color: #fff;
  font-weight: 700;
  font-size: 0.9rem;
}

.howto-step h4 {
  font-size: 1rem;
  margin-bottom: 8px;
  margin-top: 8px;
}

.howto-step p {
  color: var(--text-sub);
  font-size: 0.9rem;
  line-height: 1.6;
}

/* ============================================
   内容文章区
   ============================================ */
.article-content {
  max-width: 900px;
  margin: 0 auto;
  padding: 48px 24px;
}

.article-content h2 {
  font-size: 1.6rem;
  margin: 32px 0 16px;
  color: var(--text-main);
}

.article-content h3 {
  font-size: 1.3rem;
  margin: 24px 0 12px;
  color: var(--text-main);
}

.article-content p {
  margin-bottom: 16px;
  color: var(--text-sub);
  line-height: 1.8;
}

/* ============================================
   MCP服务前端代码区
   ============================================ */
.mcp-widget {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: 24px;
  margin: 24px 0;
}

.mcp-widget .mcp-title {
  font-size: 1rem;
  font-weight: 600;
  margin-bottom: 12px;
  color: var(--accent);
}

.mcp-widget .mcp-status {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 4px 12px;
  background: rgba(0, 212, 170, 0.1);
  border-radius: 50px;
  font-size: 0.82rem;
  color: var(--accent);
}

.mcp-widget .mcp-status .dot {
  width: 6px;
  height: 6px;
  background: var(--accent);
  border-radius: 50%;
  animation: pulse 2s infinite;
}

@keyframes pulse {
  0%, 100% { opacity: 1; }
  50% { opacity: 0.4; }
}

/* ============================================
   响应式布局
   ============================================ */
@media (max-width: 1024px) {
  .footer-grid {
    grid-template-columns: 1fr 1fr;
  }
  
  .stats-bar {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (max-width: 768px) {
  .menu-toggle {
    display: flex;
  }
  
  .main-nav {
    position: fixed;
    top: 68px;
    left: 0;
    width: 100%;
    background: rgba(13, 17, 23, 0.98);
    flex-direction: column;
    padding: 16px;
    gap: 4px;
    transform: translateY(-120%);
    transition: transform 0.3s ease;
    border-bottom: 1px solid var(--border-color);
  }
  
  .main-nav.open {
    transform: translateY(0);
  }
  
  .main-nav a {
    width: 100%;
    padding: 12px 16px;
  }
  
  .hero-content h1 {
    font-size: 1.8rem;
  }
  
  .hero-content .hero-desc {
    font-size: 1rem;
  }
  
  .video-grid {
    grid-template-columns: 1fr;
  }
  
  .stats-bar {
    grid-template-columns: repeat(2, 1fr);
    gap: 12px;
  }
  
  .footer-grid {
    grid-template-columns: 1fr;
    gap: 24px;
  }
  
  .footer-bottom {
    flex-direction: column;
    text-align: center;
  }
  
  .page-hero h1 {
    font-size: 1.6rem;
  }
  
  .section-title h2 {
    font-size: 1.5rem;
  }
}

@media (max-width: 480px) {
  .hero-banner {
    min-height: 400px;
  }
  
  .hero-content h1 {
    font-size: 1.5rem;
  }
  
  .hero-btns {
    flex-direction: column;
    align-items: center;
  }
  
  .stat-item .stat-num {
    font-size: 1.8rem;
  }
  
  .expert-grid {
    grid-template-columns: 1fr;
  }
  
  .review-grid {
    grid-template-columns: 1fr;
  }
}

/* ============================================
   懒加载占位
   ============================================ */
img[data-src] {
  opacity: 0;
  transition: opacity 0.5s ease;
}

img.loaded {
  opacity: 1;
}

/* ============================================
   动画效果
   ============================================ */
.fade-in {
  opacity: 0;
  transform: translateY(20px);
  transition: opacity 0.6s ease, transform 0.6s ease;
}

.fade-in.visible {
  opacity: 1;
  transform: translateY(0);
}

/* ============================================
   内容元信息（作者/审核/更新时间/来源）
   ============================================ */
.content-meta {
  display: flex;
  flex-wrap: wrap;
  gap: 16px;
  justify-content: center;
  margin-bottom: 32px;
  padding: 12px 20px;
  background: rgba(255, 107, 53, 0.05);
  border: 1px solid rgba(255, 107, 53, 0.12);
  border-radius: var(--radius-md);
}

.content-meta span {
  color: var(--text-sub);
  font-size: 0.85rem;
  position: relative;
  padding-left: 12px;
}

.content-meta span::before {
  content: '|';
  position: absolute;
  left: -2px;
  color: var(--border-color);
}

.content-meta span:first-child::before {
  display: none;
}

.content-meta span:first-child {
  padding-left: 0;
}

/* ============================================
   分类标签页
   ============================================ */
.category-tabs {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  justify-content: center;
  margin-bottom: 36px;
}

.category-tabs a {
  padding: 8px 20px;
  border-radius: 50px;
  font-size: 0.9rem;
  color: var(--text-sub);
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  transition: var(--transition);
}

.category-tabs a:hover,
.category-tabs a.active {
  color: #fff;
  background: var(--gradient-accent);
  border-color: var(--secondary);
}

/* ============================================
   社交分享按钮
   ============================================ */
.share-btns {
  display: flex;
  flex-wrap: wrap;
  gap: 16px;
  justify-content: center;
}

.share-btns a {
  padding: 12px 28px;
  border-radius: 50px;
  font-size: 0.95rem;
  color: var(--text-main);
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  transition: var(--transition);
}

.share-btns a:hover {
  background: var(--bg-card-hover);
  border-color: var(--secondary);
  color: var(--secondary);
  transform: translateY(-2px);
}

/* ============================================
   Section CTA按钮居中
   ============================================ */
.section-cta {
  text-align: center;
  margin-top: 40px;
}

/* ============================================
   移动端响应式增强
   ============================================ */
@media (max-width: 480px) {
  .content-meta {
    flex-direction: column;
    gap: 8px;
    align-items: center;
  }
  
  .content-meta span::before {
    display: none;
  }
  
  .content-meta span {
    padding-left: 0;
  }
  
  .category-tabs {
    gap: 6px;
  }
  
  .category-tabs a {
    padding: 6px 14px;
    font-size: 0.82rem;
  }
  
  .share-btns {
    flex-direction: column;
    align-items: center;
  }
  
  .share-btns a {
    width: 100%;
    text-align: center;
  }
}