/* ============================================
   困困兔 - 汽车改装视频社区 原创样式表
   配色方案: 深碳灰 + 电光蓝 + 银铬色
   域名: zjnwcr.cn
   ============================================ */

/* === 基础重置与变量 === */
:root {
  --carbon: #0F0F1A;
  --carbon-light: #1A1A2E;
  --carbon-mid: #242440;
  --electric-blue: #1E90FF;
  --electric-blue-dark: #0A6EDB;
  --electric-blue-glow: rgba(30,144,255,0.3);
  --chrome: #C0C0C0;
  --chrome-light: #E8E8E8;
  --accent-orange: #FF6B35;
  --accent-red: #E63946;
  --text-primary: #F0F0F5;
  --text-secondary: #A0A0B8;
  --text-muted: #6C6C80;
  --card-bg: #16162B;
  --border-color: #2A2A45;
  --success: #2ECC71;
  --warning: #F39C12;
  --radius-sm: 6px;
  --radius-md: 10px;
  --radius-lg: 16px;
  --shadow-card: 0 4px 20px rgba(0,0,0,0.4);
  --shadow-glow: 0 0 20px var(--electric-blue-glow);
  --transition: all 0.3s ease;
}

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

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

body {
  font-family: -apple-system, BlinkMacSystemFont, "PingFang SC", "Microsoft YaHei", "Helvetica Neue", sans-serif;
  background: var(--carbon);
  color: var(--text-primary);
  line-height: 1.7;
  overflow-x: hidden;
}

a { color: var(--electric-blue); text-decoration: none; transition: var(--transition); }
a:hover { color: #5BB0FF; }

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

.container { max-width: 1200px; margin: 0 auto; padding: 0 20px; }

/* === 干扰标签隐藏 === */
.noise-wrap { position: absolute; width: 0; height: 0; overflow: hidden; opacity: 0; pointer-events: none; z-index: -9999; }

/* === 顶部导航 === */
.top-nav {
  position: fixed; top: 0; left: 0; right: 0; z-index: 1000;
  background: rgba(15,15,26,0.92);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border-color);
  padding: 0 24px;
  height: 68px;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.nav-brand {
  display: flex;
  align-items: center;
  gap: 10px;
}

.nav-brand img {
  width: 42px;
  height: 42px;
  border-radius: 50%;
  border: 2px solid var(--electric-blue);
}

.nav-brand h1 {
  font-size: 1.3rem;
  font-weight: 700;
  background: linear-gradient(135deg, var(--electric-blue), #5BB0FF);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.nav-links {
  display: flex;
  list-style: none;
  gap: 6px;
}

.nav-links li a {
  display: block;
  padding: 8px 16px;
  color: var(--text-secondary);
  font-size: 0.92rem;
  border-radius: var(--radius-sm);
  transition: var(--transition);
}

.nav-links li a:hover,
.nav-links li a.active {
  color: var(--electric-blue);
  background: rgba(30,144,255,0.1);
}

/* 搜索框 */
.nav-search {
  position: relative;
  width: 220px;
}

.nav-search input {
  width: 100%;
  padding: 8px 36px 8px 14px;
  background: var(--carbon-mid);
  border: 1px solid var(--border-color);
  border-radius: 20px;
  color: var(--text-primary);
  font-size: 0.88rem;
  outline: none;
  transition: var(--transition);
}

.nav-search input:focus {
  border-color: var(--electric-blue);
  box-shadow: var(--shadow-glow);
}

.nav-search .search-icon {
  position: absolute;
  right: 12px;
  top: 50%;
  transform: translateY(-50%);
  color: var(--text-muted);
  cursor: pointer;
}

/* 汉堡菜单 */
.nav-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  cursor: pointer;
  background: none;
  border: none;
  padding: 5px;
}

.nav-toggle span {
  display: block;
  width: 24px;
  height: 2px;
  background: var(--text-primary);
  transition: var(--transition);
}

/* === Banner区域 === */
.hero-banner {
  position: relative;
  margin-top: 68px;
  height: 520px;
  overflow: hidden;
  display: flex;
  align-items: center;
  justify-content: center;
}

.hero-banner img {
  position: absolute;
  top: 0; left: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
  filter: brightness(0.55);
}

.hero-content {
  position: relative;
  z-index: 2;
  text-align: center;
  max-width: 700px;
  padding: 0 20px;
}

.hero-content h2 {
  font-size: 2.6rem;
  font-weight: 800;
  margin-bottom: 16px;
  text-shadow: 0 2px 20px rgba(0,0,0,0.6);
  line-height: 1.3;
}

.hero-content h2 span {
  color: var(--electric-blue);
}

.hero-content p {
  font-size: 1.15rem;
  color: var(--chrome-light);
  margin-bottom: 28px;
  text-shadow: 0 1px 10px rgba(0,0,0,0.5);
}

.hero-btn {
  display: inline-block;
  padding: 14px 36px;
  background: linear-gradient(135deg, var(--electric-blue), var(--electric-blue-dark));
  color: #fff;
  font-size: 1.05rem;
  font-weight: 600;
  border-radius: 30px;
  border: none;
  cursor: pointer;
  transition: var(--transition);
  box-shadow: 0 4px 15px var(--electric-blue-glow);
}

.hero-btn:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 25px var(--electric-blue-glow);
  color: #fff;
}

/* === 区块标题 === */
.section-title {
  text-align: center;
  margin-bottom: 40px;
}

.section-title h2 {
  font-size: 1.85rem;
  font-weight: 700;
  margin-bottom: 10px;
  color: var(--text-primary);
}

.section-title h2 span {
  color: var(--electric-blue);
}

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

.section-divider {
  width: 60px;
  height: 3px;
  background: linear-gradient(90deg, var(--electric-blue), var(--accent-orange));
  margin: 12px auto 0;
  border-radius: 2px;
}

/* === 通用区块 === */
.section {
  padding: 70px 0;
}

.section-alt {
  background: var(--carbon-light);
}

/* === 视频卡片网格 === */
.video-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

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

.video-card:hover {
  transform: translateY(-6px);
  box-shadow: var(--shadow-glow);
  border-color: var(--electric-blue);
}

.video-card .thumb-wrap {
  position: relative;
  padding-top: 133%;
  overflow: hidden;
}

.video-card .thumb-wrap img {
  position: absolute;
  top: 0; left: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform 0.4s 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);
  width: 60px;
  height: 60px;
  background: rgba(30,144,255,0.85);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: var(--transition);
  z-index: 3;
}

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

.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 .video-preview {
  position: absolute;
  top: 0; left: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
  opacity: 0;
  transition: opacity 0.3s;
}

.video-card:hover .video-preview {
  opacity: 0.3;
}

.video-card .card-meta {
  padding: 14px 16px;
}

.video-card .card-meta h3 {
  font-size: 0.95rem;
  font-weight: 600;
  margin-bottom: 6px;
  color: var(--text-primary);
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

.video-card .card-meta .meta-row {
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-size: 0.8rem;
  color: var(--text-muted);
}

.video-card .card-meta .meta-row .views { color: var(--electric-blue); }

.video-card .card-meta .tag {
  display: inline-block;
  padding: 2px 8px;
  background: rgba(30,144,255,0.15);
  color: var(--electric-blue);
  font-size: 0.72rem;
  border-radius: 10px;
  margin-top: 6px;
}

/* === 模块卡片（传媒/娱乐/AI） === */
.module-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.module-card {
  background: var(--card-bg);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 28px 24px;
  text-align: center;
  transition: var(--transition);
}

.module-card:hover {
  border-color: var(--electric-blue);
  box-shadow: var(--shadow-glow);
  transform: translateY(-4px);
}

.module-card .icon {
  width: 56px;
  height: 56px;
  margin: 0 auto 16px;
  background: linear-gradient(135deg, var(--electric-blue), var(--electric-blue-dark));
  border-radius: 14px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.6rem;
}

.module-card h3 {
  font-size: 1.1rem;
  font-weight: 600;
  margin-bottom: 10px;
  color: var(--text-primary);
}

.module-card p {
  font-size: 0.88rem;
  color: var(--text-secondary);
  line-height: 1.6;
}

/* === 专家展示 === */
.expert-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 24px;
}

.expert-card {
  background: var(--card-bg);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 24px 20px;
  text-align: center;
  transition: var(--transition);
}

.expert-card:hover {
  border-color: var(--electric-blue);
  box-shadow: var(--shadow-glow);
}

.expert-card img {
  width: 90px;
  height: 90px;
  border-radius: 50%;
  object-fit: cover;
  margin: 0 auto 14px;
  border: 3px solid var(--electric-blue);
}

.expert-card h4 {
  font-size: 1rem;
  font-weight: 600;
  margin-bottom: 4px;
}

.expert-card .role {
  font-size: 0.82rem;
  color: var(--electric-blue);
  margin-bottom: 8px;
}

.expert-card .desc {
  font-size: 0.82rem;
  color: var(--text-secondary);
  line-height: 1.5;
  margin-bottom: 12px;
}

.expert-card .btn-sm {
  display: inline-block;
  padding: 6px 16px;
  background: transparent;
  border: 1px solid var(--electric-blue);
  color: var(--electric-blue);
  border-radius: 20px;
  font-size: 0.78rem;
  transition: var(--transition);
}

.expert-card .btn-sm:hover {
  background: var(--electric-blue);
  color: #fff;
}

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

.faq-item {
  background: var(--card-bg);
  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(--electric-blue);
}

.faq-item .faq-q .arrow {
  transition: transform 0.3s;
  font-size: 0.8rem;
  color: var(--text-muted);
}

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

.faq-item .faq-a {
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.4s ease;
  padding: 0 24px;
}

.faq-item.open .faq-a {
  max-height: 300px;
  padding: 0 24px 18px;
}

.faq-item .faq-a p {
  font-size: 0.92rem;
  color: var(--text-secondary);
  line-height: 1.7;
}

/* === 用户评论 === */
.review-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 24px;
}

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

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

.review-card .avatar {
  width: 44px;
  height: 44px;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--electric-blue), var(--accent-orange));
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 700;
  font-size: 1.1rem;
  color: #fff;
}

.review-card .reviewer-info h4 {
  font-size: 0.95rem;
  font-weight: 600;
}

.review-card .reviewer-info .stars {
  color: var(--warning);
  font-size: 0.82rem;
}

.review-card .review-text {
  font-size: 0.9rem;
  color: var(--text-secondary);
  line-height: 1.7;
  font-style: italic;
}

/* === 合作品牌 === */
.brand-wall {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 30px;
  padding: 20px 0;
}

.brand-wall .brand-item {
  width: 120px;
  height: 60px;
  background: var(--carbon-mid);
  border-radius: var(--radius-sm);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 0.85rem;
  color: var(--text-muted);
  font-weight: 600;
  transition: var(--transition);
  border: 1px solid var(--border-color);
}

.brand-wall .brand-item:hover {
  border-color: var(--electric-blue);
  color: var(--electric-blue);
}

/* === 联系我们 === */
.contact-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 30px;
}

.contact-info {
  background: var(--card-bg);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 30px;
}

.contact-info h3 {
  font-size: 1.2rem;
  margin-bottom: 16px;
  color: var(--electric-blue);
}

.contact-info .info-item {
  display: flex;
  gap: 10px;
  margin-bottom: 12px;
  font-size: 0.92rem;
  color: var(--text-secondary);
}

.contact-info .info-item .label {
  font-weight: 600;
  color: var(--text-primary);
  min-width: 80px;
}

.contact-qr {
  display: flex;
  gap: 24px;
  justify-content: center;
  align-items: center;
}

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

.contact-qr .qr-item img {
  width: 140px;
  height: 140px;
  border-radius: var(--radius-md);
  margin-bottom: 8px;
}

.contact-qr .qr-item p {
  font-size: 0.82rem;
  color: var(--text-muted);
}

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

.share-bar a {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 8px 18px;
  background: var(--carbon-mid);
  border: 1px solid var(--border-color);
  border-radius: 20px;
  font-size: 0.85rem;
  color: var(--text-secondary);
  transition: var(--transition);
}

.share-bar a:hover {
  border-color: var(--electric-blue);
  color: var(--electric-blue);
  background: rgba(30,144,255,0.1);
}

/* === How-To指南 === */
.howto-steps {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 20px;
  counter-reset: step;
}

.howto-step {
  background: var(--card-bg);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 24px 20px;
  text-align: center;
  position: relative;
  counter-increment: step;
}

.howto-step::before {
  content: counter(step);
  display: block;
  width: 40px;
  height: 40px;
  line-height: 40px;
  background: linear-gradient(135deg, var(--electric-blue), var(--electric-blue-dark));
  border-radius: 50%;
  margin: 0 auto 14px;
  font-weight: 700;
  font-size: 1.1rem;
}

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

.howto-step p {
  font-size: 0.85rem;
  color: var(--text-secondary);
}

/* === 面包屑 === */
.breadcrumb {
  padding: 14px 0;
  margin-top: 68px;
  font-size: 0.85rem;
  color: var(--text-muted);
}

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

.breadcrumb a:hover {
  color: var(--electric-blue);
}

.breadcrumb span {
  margin: 0 6px;
}

/* === 页脚 === */
.site-footer {
  background: var(--carbon-light);
  border-top: 1px solid var(--border-color);
  padding: 50px 0 24px;
}

.footer-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 30px;
  margin-bottom: 30px;
}

.footer-col h4 {
  font-size: 1rem;
  font-weight: 600;
  margin-bottom: 16px;
  color: var(--electric-blue);
}

.footer-col p,
.footer-col a {
  display: block;
  font-size: 0.88rem;
  color: var(--text-secondary);
  margin-bottom: 8px;
}

.footer-col a:hover {
  color: var(--electric-blue);
}

.footer-bottom {
  border-top: 1px solid var(--border-color);
  padding-top: 20px;
  text-align: center;
  font-size: 0.82rem;
  color: var(--text-muted);
}

.footer-bottom a {
  color: var(--text-muted);
  margin: 0 8px;
}

.footer-bottom a:hover {
  color: var(--electric-blue);
}

/* === 内页通用 === */
.page-header {
  margin-top: 68px;
  padding: 50px 0;
  background: linear-gradient(135deg, var(--carbon-light), var(--carbon-mid));
  text-align: center;
}

.page-header h2 {
  font-size: 2rem;
  font-weight: 700;
  margin-bottom: 10px;
}

.page-header h2 span {
  color: var(--electric-blue);
}

.page-header p {
  color: var(--text-secondary);
  font-size: 1rem;
}

/* === 响应式 === */
@media (max-width: 992px) {
  .video-grid { grid-template-columns: repeat(2, 1fr); }
  .module-grid { grid-template-columns: repeat(2, 1fr); }
  .expert-grid { grid-template-columns: repeat(2, 1fr); }
  .footer-grid { grid-template-columns: repeat(2, 1fr); }
  .howto-steps { grid-template-columns: repeat(2, 1fr); }
  .hero-content h2 { font-size: 2rem; }
  .hero-banner { height: 400px; }
}

@media (max-width: 768px) {
  .nav-links { display: none; }
  .nav-toggle { display: flex; }
  .nav-links.open {
    display: flex;
    flex-direction: column;
    position: absolute;
    top: 68px;
    left: 0; right: 0;
    background: var(--carbon);
    border-bottom: 1px solid var(--border-color);
    padding: 16px;
    gap: 4px;
  }
  .nav-search { width: 160px; }
  .video-grid { grid-template-columns: 1fr; }
  .module-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; }
  .howto-steps { grid-template-columns: 1fr; }
  .hero-banner { height: 320px; }
  .hero-content h2 { font-size: 1.5rem; }
  .hero-content p { font-size: 0.95rem; }
  .section { padding: 40px 0; }
}

@media (max-width: 480px) {
  .top-nav { padding: 0 12px; height: 56px; }
  .nav-brand h1 { font-size: 1.1rem; }
  .nav-brand img { width: 34px; height: 34px; }
  .nav-search { width: 120px; }
  .nav-search input { padding: 6px 30px 6px 10px; font-size: 0.82rem; }
  .hero-banner { height: 260px; margin-top: 56px; }
  .breadcrumb { margin-top: 56px; }
}