/* ==========================================================================
   海角 修车改装视频社区 (y990o9.cn) - 原创竞技赛博风格样式表
   全站完全原创设计：赛道黑金、碳纤维暗调、钛合金、竞技高光橙与赛博青蓝
   ========================================================================== */

:root {
  --bg-primary: #0a0d12;
  --bg-secondary: #121721;
  --bg-card: rgba(22, 28, 38, 0.78);
  --bg-card-hover: rgba(28, 36, 50, 0.92);
  --border-color: rgba(255, 255, 255, 0.08);
  --border-focus: #ff5500;
  
  --brand-orange: #ff5500;
  --brand-orange-light: #ff772e;
  --brand-gold: #ffaa00;
  --brand-cyan: #00e5ff;
  --brand-cyan-glow: rgba(0, 229, 255, 0.35);
  
  --text-main: #f5f7fa;
  --text-muted: #9aa5b5;
  --text-sub: #697486;
  
  --font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  --radius-sm: 6px;
  --radius-md: 10px;
  --radius-lg: 16px;
  --shadow-card: 0 10px 30px rgba(0, 0, 0, 0.45);
  --shadow-glow: 0 0 25px rgba(255, 85, 0, 0.28);
}

* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

body {
  background-color: var(--bg-primary);
  color: var(--text-main);
  font-family: var(--font-family);
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
  background-image: 
    radial-gradient(circle at 15% 15%, rgba(255, 85, 0, 0.04) 0%, transparent 40%),
    radial-gradient(circle at 85% 85%, rgba(0, 229, 255, 0.04) 0%, transparent 40%),
    linear-gradient(rgba(255, 255, 255, 0.015) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255, 255, 255, 0.015) 1px, transparent 1px);
  background-size: 100% 100%, 100% 100%, 36px 36px, 36px 36px;
}

a {
  color: inherit;
  text-decoration: none;
  transition: all 0.25s ease;
}

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

/* 顶部全局通栏与导航 */
.site-header {
  position: sticky;
  top: 0;
  z-index: 1000;
  background: rgba(10, 13, 18, 0.92);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border-color);
}

.header-inner {
  max-width: 1380px;
  margin: 0 auto;
  padding: 14px 24px;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.brand-badge {
  display: flex;
  align-items: center;
  gap: 14px;
}

.brand-logo-img {
  width: 46px;
  height: 46px;
  border-radius: var(--radius-sm);
  border: 1px solid var(--brand-orange);
  box-shadow: 0 0 12px rgba(255, 85, 0, 0.35);
}

.brand-titles h1, .brand-titles .h1-logo {
  font-size: 24px;
  font-weight: 800;
  letter-spacing: 1px;
  color: #fff;
  display: flex;
  align-items: center;
  gap: 8px;
}

.brand-titles .brand-accent {
  color: var(--brand-orange);
  font-weight: 900;
}

.brand-subtitle-tag {
  font-size: 12px;
  color: var(--text-muted);
}

.site-nav {
  display: flex;
  align-items: center;
  gap: 24px;
}

.nav-link {
  font-size: 15px;
  font-weight: 600;
  color: var(--text-muted);
  position: relative;
  padding: 6px 2px;
}

.nav-link:hover, .nav-link.active {
  color: var(--brand-orange);
}

.nav-link.active::after {
  content: "";
  position: absolute;
  bottom: 0;
  left: 0;
  width: 100%;
  height: 2px;
  background: var(--brand-orange);
  box-shadow: 0 0 8px var(--brand-orange);
}

.header-actions {
  display: flex;
  align-items: center;
  gap: 12px;
}

.btn-primary {
  background: linear-gradient(135deg, var(--brand-orange), #d94400);
  color: #fff;
  padding: 8px 18px;
  border-radius: var(--radius-sm);
  font-weight: 700;
  font-size: 14px;
  border: 1px solid rgba(255, 255, 255, 0.15);
  box-shadow: 0 4px 16px rgba(255, 85, 0, 0.35);
  cursor: pointer;
  display: inline-flex;
  align-items: center;
  gap: 6px;
}

.btn-primary:hover {
  background: linear-gradient(135deg, var(--brand-orange-light), var(--brand-orange));
  box-shadow: 0 6px 20px rgba(255, 85, 0, 0.55);
}

.btn-secondary {
  background: rgba(255, 255, 255, 0.05);
  color: var(--text-main);
  padding: 8px 16px;
  border-radius: var(--radius-sm);
  font-weight: 600;
  font-size: 14px;
  border: 1px solid var(--border-color);
  cursor: pointer;
}

.btn-secondary:hover {
  background: rgba(255, 255, 255, 0.1);
  border-color: var(--brand-cyan);
  color: var(--brand-cyan);
}

/* 导航下方模拟搜索条 */
.search-bar-wrap {
  background: #0f141d;
  border-bottom: 1px solid var(--border-color);
  padding: 12px 24px;
}

.search-container {
  max-width: 1380px;
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 20px;
}

.search-box-form {
  position: relative;
  flex: 1;
  max-width: 680px;
}

.search-input {
  width: 100%;
  background: rgba(22, 28, 38, 0.85);
  border: 1px solid rgba(255, 255, 255, 0.12);
  border-radius: 24px;
  padding: 10px 48px 10px 20px;
  color: #fff;
  font-size: 14px;
  outline: none;
  transition: all 0.2s ease;
}

.search-input:focus {
  border-color: var(--brand-orange);
  box-shadow: 0 0 12px rgba(255, 85, 0, 0.25);
  background: #18202d;
}

.search-submit-btn {
  position: absolute;
  right: 6px;
  top: 50%;
  transform: translateY(-50%);
  background: var(--brand-orange);
  border: none;
  color: #fff;
  border-radius: 50%;
  width: 32px;
  height: 32px;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 14px;
}

.search-hot-tags {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 13px;
  color: var(--text-sub);
}

.hot-tag-item {
  color: var(--text-muted);
  cursor: pointer;
  padding: 3px 8px;
  border-radius: var(--radius-sm);
  background: rgba(255, 255, 255, 0.04);
}

.hot-tag-item:hover {
  color: var(--brand-cyan);
  background: rgba(0, 229, 255, 0.1);
}

/* 首屏 Banner 英雄区 */
.hero-banner-section {
  position: relative;
  min-height: 580px;
  display: flex;
  align-items: center;
  background-size: cover;
  background-position: center;
  background-repeat: no-repeat;
  border-bottom: 1px solid var(--border-color);
  overflow: hidden;
}

.hero-overlay {
  position: absolute;
  inset: 0;
  background: linear-gradient(180deg, rgba(10, 13, 18, 0.65) 0%, rgba(10, 13, 18, 0.92) 100%),
              radial-gradient(circle at 70% 30%, rgba(255, 85, 0, 0.15) 0%, transparent 60%);
}

.hero-content {
  position: relative;
  z-index: 10;
  max-width: 1380px;
  margin: 0 auto;
  padding: 70px 24px;
}

.hero-pill-badge {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  background: rgba(255, 85, 0, 0.12);
  border: 1px solid rgba(255, 85, 0, 0.35);
  color: var(--brand-orange-light);
  padding: 6px 14px;
  border-radius: 30px;
  font-size: 13px;
  font-weight: 700;
  margin-bottom: 20px;
  text-transform: uppercase;
}

.hero-h1-title {
  font-size: 44px;
  font-weight: 900;
  line-height: 1.25;
  color: #fff;
  margin-bottom: 16px;
  max-width: 950px;
}

.hero-h1-title .highlight {
  color: var(--brand-orange);
  text-shadow: 0 0 15px rgba(255, 85, 0, 0.4);
}

.hero-subtitle-desc {
  font-size: 18px;
  color: var(--text-muted);
  max-width: 820px;
  margin-bottom: 32px;
  line-height: 1.7;
}

.hero-stats-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 20px;
  max-width: 880px;
  margin-top: 36px;
}

.stat-item-box {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  padding: 16px;
  border-radius: var(--radius-md);
  backdrop-filter: blur(8px);
}

.stat-num {
  font-size: 28px;
  font-weight: 800;
  color: #fff;
  font-family: monospace;
}

.stat-num span {
  color: var(--brand-orange);
}

.stat-desc {
  font-size: 13px;
  color: var(--text-muted);
}

/* 核心布局容器 */
.main-wrapper {
  max-width: 1380px;
  margin: 0 auto;
  padding: 50px 24px;
}

.section-head-box {
  margin-bottom: 32px;
  display: flex;
  align-items: flex-end;
  justify-content: space-between;
  border-left: 4px solid var(--brand-orange);
  padding-left: 16px;
}

.section-head-box h2 {
  font-size: 28px;
  font-weight: 800;
  color: #fff;
}

.section-head-box p {
  color: var(--text-muted);
  font-size: 14px;
  margin-top: 4px;
}

.section-more-link {
  font-size: 14px;
  color: var(--brand-cyan);
  font-weight: 600;
}

.section-more-link:hover {
  text-decoration: underline;
}

/* 视频卡片体系与动态播放浮层 */
.video-cards-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.video-card-item {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  overflow: hidden;
  box-shadow: var(--shadow-card);
  transition: all 0.3s cubic-bezier(0.165, 0.84, 0.44, 1);
  display: flex;
  flex-direction: column;
  position: relative;
}

.video-card-item:hover {
  transform: translateY(-6px);
  border-color: rgba(255, 85, 0, 0.4);
  box-shadow: 0 14px 35px rgba(0, 0, 0, 0.6), 0 0 20px rgba(255, 85, 0, 0.2);
}

.video-thumb-container {
  position: relative;
  width: 100%;
  aspect-ratio: 16 / 9;
  overflow: hidden;
  background: #000;
}

.video-thumb-img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform 0.5s ease;
}

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

.video-play-overlay {
  position: absolute;
  inset: 0;
  background: rgba(10, 13, 18, 0.4);
  display: flex;
  align-items: center;
  justify-content: center;
  opacity: 0;
  transition: opacity 0.25s ease;
}

.video-card-item:hover .video-play-overlay {
  opacity: 1;
}

.play-icon-circle {
  width: 54px;
  height: 54px;
  background: rgba(255, 85, 0, 0.9);
  border: 2px solid #fff;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  color: #fff;
  font-size: 20px;
  box-shadow: 0 0 20px rgba(255, 85, 0, 0.8);
  transform: scale(0.8);
  transition: transform 0.25s ease;
}

.video-card-item:hover .play-icon-circle {
  transform: scale(1);
}

.video-tag-pill {
  position: absolute;
  top: 10px;
  left: 10px;
  background: rgba(11, 14, 20, 0.85);
  border: 1px solid rgba(255, 255, 255, 0.15);
  color: var(--brand-cyan);
  font-size: 11px;
  padding: 3px 8px;
  border-radius: 4px;
  font-weight: 700;
}

.video-duration-pill {
  position: absolute;
  bottom: 10px;
  right: 10px;
  background: rgba(0, 0, 0, 0.75);
  color: #fff;
  font-size: 11px;
  padding: 2px 6px;
  border-radius: 4px;
  font-family: monospace;
}

.video-card-body {
  padding: 18px;
  flex: 1;
  display: flex;
  flex-direction: column;
}

.video-title {
  font-size: 17px;
  font-weight: 700;
  color: #fff;
  line-height: 1.4;
  margin-bottom: 8px;
}

.video-desc {
  font-size: 13px;
  color: var(--text-muted);
  line-height: 1.55;
  margin-bottom: 14px;
  flex: 1;
}

.video-meta-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  border-top: 1px solid rgba(255, 255, 255, 0.06);
  padding-top: 12px;
  font-size: 12px;
  color: var(--text-sub);
}

.video-stats {
  display: flex;
  gap: 12px;
}

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

/* 短视频/竖屏/TikTok 娱乐专区 */
.tiktok-video-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 20px;
}

.tiktok-card {
  position: relative;
  aspect-ratio: 9 / 16;
  border-radius: var(--radius-md);
  overflow: hidden;
  background: #111;
  border: 1px solid var(--border-color);
  box-shadow: var(--shadow-card);
  cursor: pointer;
}

.tiktok-bg-img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform 0.4s ease;
}

.tiktok-card:hover .tiktok-bg-img {
  transform: scale(1.06);
}

.tiktok-mask {
  position: absolute;
  inset: 0;
  background: linear-gradient(180deg, rgba(0,0,0,0.1) 40%, rgba(10,13,18,0.95) 100%);
  display: flex;
  flex-direction: column;
  justify-content: flex-end;
  padding: 16px;
}

.tiktok-title {
  font-size: 15px;
  font-weight: 700;
  color: #fff;
  margin-bottom: 6px;
}

.tiktok-stats {
  font-size: 12px;
  color: var(--brand-orange-light);
  display: flex;
  justify-content: space-between;
}

/* AI 赋能科技专区 */
.ai-tech-container {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 30px;
  align-items: center;
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 36px;
  position: relative;
  overflow: hidden;
}

.ai-tech-container::before {
  content: "";
  position: absolute;
  top: -50px;
  right: -50px;
  width: 260px;
  height: 260px;
  background: radial-gradient(circle, rgba(0, 229, 255, 0.15) 0%, transparent 70%);
  pointer-events: none;
}

.ai-feature-list {
  display: flex;
  flex-direction: column;
  gap: 18px;
  margin-top: 24px;
}

.ai-feature-item {
  display: flex;
  gap: 14px;
}

.ai-icon-box {
  width: 44px;
  height: 44px;
  border-radius: var(--radius-sm);
  background: rgba(0, 229, 255, 0.12);
  border: 1px solid rgba(0, 229, 255, 0.3);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--brand-cyan);
  font-weight: 800;
  flex-shrink: 0;
}

.ai-feature-info h4 {
  font-size: 16px;
  color: #fff;
  margin-bottom: 4px;
}

.ai-feature-info p {
  font-size: 13px;
  color: var(--text-muted);
}

/* 专家展示板块 */
.experts-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 20px;
}

.expert-card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: 20px;
  text-align: center;
  transition: all 0.25s ease;
}

.expert-card:hover {
  border-color: var(--brand-cyan);
  transform: translateY(-4px);
}

.expert-avatar {
  width: 90px;
  height: 90px;
  border-radius: 50%;
  margin: 0 auto 16px;
  object-fit: cover;
  border: 2px solid var(--brand-orange);
}

.expert-name {
  font-size: 18px;
  font-weight: 700;
  color: #fff;
  margin-bottom: 4px;
}

.expert-role {
  font-size: 13px;
  color: var(--brand-cyan);
  margin-bottom: 12px;
}

.expert-bio {
  font-size: 12px;
  color: var(--text-muted);
  line-height: 1.5;
  margin-bottom: 16px;
}

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

/* 合作改装品牌墙 */
.brand-wall-grid {
  display: grid;
  grid-template-columns: repeat(6, 1fr);
  gap: 16px;
  margin-bottom: 30px;
}

.brand-partner-item {
  background: rgba(255, 255, 255, 0.03);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-sm);
  padding: 16px;
  text-align: center;
  font-weight: 800;
  color: var(--text-muted);
  font-size: 15px;
  letter-spacing: 1px;
  transition: all 0.2s ease;
}

.brand-partner-item:hover {
  background: rgba(255, 85, 0, 0.08);
  border-color: var(--brand-orange);
  color: #fff;
}

/* How-To 指南与 FAQ */
.howto-faq-wrap {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 30px;
}

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

.howto-steps {
  display: flex;
  flex-direction: column;
  gap: 16px;
  margin-top: 18px;
}

.howto-step-item {
  display: flex;
  gap: 14px;
}

.step-number {
  width: 32px;
  height: 32px;
  border-radius: 50%;
  background: var(--brand-orange);
  color: #fff;
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 800;
  font-size: 14px;
  flex-shrink: 0;
}

.faq-container {
  display: flex;
  flex-direction: column;
  gap: 12px;
}

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

.faq-question {
  padding: 14px 18px;
  font-weight: 700;
  font-size: 15px;
  cursor: pointer;
  display: flex;
  justify-content: space-between;
  align-items: center;
  color: #fff;
}

.faq-question:hover {
  color: var(--brand-orange);
}

.faq-answer {
  padding: 0 18px 14px;
  font-size: 13px;
  color: var(--text-muted);
  line-height: 1.6;
}

/* 用户与口碑 */
.reviews-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 20px;
}

.review-card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: 20px;
}

.review-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 12px;
}

.reviewer-name {
  font-weight: 700;
  color: #fff;
}

.reviewer-stars {
  color: var(--brand-gold);
}

.review-text {
  font-size: 13px;
  color: var(--text-muted);
  line-height: 1.6;
  margin-bottom: 12px;
}

.review-vehicle-tag {
  font-size: 12px;
  color: var(--brand-cyan);
  font-weight: 600;
}

/* 实体修车改装公司与社区联系 */
.contact-section-wrap {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 30px;
  background: var(--bg-secondary);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 36px;
}

.contact-company-info h3 {
  font-size: 22px;
  color: #fff;
  margin-bottom: 14px;
}

.contact-detail-list {
  display: flex;
  flex-direction: column;
  gap: 12px;
  margin-top: 18px;
  font-size: 14px;
  color: var(--text-muted);
}

.contact-detail-list strong {
  color: #fff;
}

.qr-code-cards {
  display: flex;
  gap: 24px;
  align-items: center;
  justify-content: center;
  background: rgba(0, 0, 0, 0.35);
  border-radius: var(--radius-md);
  padding: 20px;
}

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

.qr-img {
  width: 140px;
  height: 140px;
  border-radius: var(--radius-sm);
  background: #fff;
  padding: 6px;
  margin-bottom: 8px;
}

.qr-label {
  font-size: 12px;
  color: var(--text-muted);
  font-weight: 600;
}

/* 社交分享栏与前端 MCP 体验区 */
.social-mcp-section {
  margin-top: 40px;
  background: rgba(22, 28, 38, 0.5);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: 24px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 20px;
}

.share-buttons-wrap {
  display: flex;
  align-items: center;
  gap: 12px;
}

.share-btn {
  background: rgba(255, 255, 255, 0.05);
  border: 1px solid var(--border-color);
  color: #fff;
  padding: 6px 14px;
  border-radius: var(--radius-sm);
  font-size: 13px;
  cursor: pointer;
  transition: all 0.2s ease;
}

.share-btn:hover {
  background: var(--brand-orange);
  border-color: var(--brand-orange);
}

.mcp-code-snippet {
  font-family: monospace;
  font-size: 12px;
  color: var(--brand-cyan);
  background: rgba(0, 0, 0, 0.45);
  padding: 8px 14px;
  border-radius: var(--radius-sm);
  border: 1px solid rgba(0, 229, 255, 0.2);
}

/* 全局页脚 */
.site-footer {
  background: #080a0e;
  border-top: 1px solid var(--border-color);
  padding: 48px 24px 30px;
  margin-top: 60px;
}

.footer-inner {
  max-width: 1380px;
  margin: 0 auto;
}

.footer-main-row {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1.5fr;
  gap: 40px;
  margin-bottom: 36px;
}

.footer-brand-box p {
  color: var(--text-muted);
  font-size: 13px;
  line-height: 1.7;
  margin-top: 14px;
  max-width: 360px;
}

.footer-links-col h4 {
  font-size: 16px;
  color: #fff;
  margin-bottom: 16px;
}

.footer-nav-list {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 8px;
  font-size: 13px;
  color: var(--text-muted);
}

.footer-nav-list a:hover {
  color: var(--brand-orange);
}

.footer-bottom-bar {
  border-top: 1px solid rgba(255, 255, 255, 0.06);
  padding-top: 24px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-size: 13px;
  color: var(--text-sub);
  flex-wrap: wrap;
  gap: 12px;
}

.footer-update-time {
  color: var(--brand-cyan);
  font-family: monospace;
}

/* 面包屑导航与内页通用 */
.breadcrumbs-bar {
  background: rgba(18, 23, 33, 0.7);
  border-bottom: 1px solid var(--border-color);
  padding: 10px 24px;
  font-size: 13px;
  color: var(--text-sub);
}

.breadcrumbs-inner {
  max-width: 1380px;
  margin: 0 auto;
  display: flex;
  align-items: center;
  gap: 8px;
}

.breadcrumbs-inner a {
  color: var(--text-muted);
}

.breadcrumbs-inner a:hover {
  color: var(--brand-orange);
}

.breadcrumbs-current {
  color: var(--brand-orange);
  font-weight: 700;
}

/* 模态框/弹窗 */
.modal-overlay {
  position: fixed;
  inset: 0;
  background: rgba(0, 0, 0, 0.75);
  backdrop-filter: blur(4px);
  z-index: 2000;
  display: none;
  align-items: center;
  justify-content: center;
  padding: 20px;
}

.modal-overlay.active {
  display: flex;
}

.modal-box {
  background: var(--bg-secondary);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  max-width: 520px;
  width: 100%;
  padding: 24px;
  position: relative;
  box-shadow: 0 20px 40px rgba(0, 0, 0, 0.8);
}

.modal-close-btn {
  position: absolute;
  top: 14px;
  right: 14px;
  background: none;
  border: none;
  color: var(--text-muted);
  font-size: 22px;
  cursor: pointer;
}

/* 响应式适配 (手机、平板) */
@media (max-width: 1024px) {
  .video-cards-grid, .reviews-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  .tiktok-video-grid, .experts-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  .brand-wall-grid {
    grid-template-columns: repeat(3, 1fr);
  }
  .ai-tech-container, .howto-faq-wrap, .contact-section-wrap {
    grid-template-columns: 1fr;
  }
  .footer-main-row {
    grid-template-columns: 1fr 1fr;
  }
}

@media (max-width: 768px) {
  .header-inner {
    flex-direction: column;
    gap: 14px;
  }
  .site-nav {
    flex-wrap: wrap;
    justify-content: center;
    gap: 14px;
  }
  .search-container {
    flex-direction: column;
    align-items: stretch;
  }
  .hero-h1-title {
    font-size: 28px;
  }
  .hero-stats-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  .video-cards-grid, .tiktok-video-grid, .experts-grid, .reviews-grid {
    grid-template-columns: 1fr;
  }
  .footer-main-row {
    grid-template-columns: 1fr;
  }
  .qr-code-cards {
    flex-direction: column;
  }
}