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

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "Microsoft YaHei", sans-serif;
  line-height: 1.6;
  color: #333;
  background: #f5f5f5;
}

body.ui-style-14 {
  --primary-color: #005EB8;
  --secondary-color: #FF6B35;
  --text-color: #2c3e50;
  --bg-color: #ffffff;
  --border-color: #e0e0e0;
  --hover-color: #0073e6;
}

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

.site-header {
  background: var(--bg-color);
  border-bottom: 1px solid var(--border-color);
  position: sticky;
  top: 0;
  z-index: 100;
  box-shadow: 0 2px 4px rgba(0,0,0,0.05);
}

.header-container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 20px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 60px;
}

.logo a {
  font-size: 24px;
  font-weight: 700;
  color: var(--primary-color);
  text-decoration: none;
  white-space: nowrap;
}

.main-nav {
  display: flex;
  gap: 8px;
  align-items: center;
}

.main-nav a {
  padding: 8px 16px;
  color: var(--text-color);
  text-decoration: none;
  border-radius: 4px;
  transition: all 0.3s;
  font-size: 15px;
  white-space: nowrap;
}

.main-nav a:hover,
.main-nav a.active {
  background: var(--primary-color);
  color: white;
}

.main-content {
  min-height: calc(100vh - 180px);
}

.hero-section {
  background: linear-gradient(135deg, var(--primary-color), #0073e6);
  color: white;
  padding: 60px 20px;
  text-align: center;
}

.hero-title {
  font-size: 32px;
  font-weight: 700;
  margin-bottom: 16px;
  line-height: 1.3;
}

.hero-desc {
  font-size: 16px;
  max-width: 800px;
  margin: 0 auto;
  line-height: 1.8;
  opacity: 0.95;
}

.intro-section {
  background: white;
  padding: 40px 20px;
  margin: 20px 0;
}

.site-intro {
  max-width: 900px;
  margin: 0 auto;
  text-align: center;
  font-size: 15px;
  line-height: 1.8;
  color: #555;
}

.video-section {
  padding: 40px 0;
}

.section-header {
  margin-bottom: 24px;
}

.section-title {
  font-size: 24px;
  font-weight: 600;
  color: var(--text-color);
  padding-bottom: 12px;
  border-bottom: 3px solid var(--primary-color);
  display: inline-block;
}

.video-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(260px, 1fr));
  gap: 24px;
}

.video-card {
  background: white;
  border-radius: 8px;
  overflow: hidden;
  box-shadow: 0 2px 8px rgba(0,0,0,0.08);
  transition: transform 0.3s, box-shadow 0.3s;
}

.video-card:hover {
  transform: translateY(-4px);
  box-shadow: 0 4px 16px rgba(0,0,0,0.12);
}

.video-card__link {
  text-decoration: none;
  color: inherit;
  display: block;
}

.video-cover {
  position: relative;
  padding-top: 140%;
  overflow: hidden;
  background: #f0f0f0;
}

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

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

.play-overlay {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  display: flex;
  align-items: center;
  justify-content: center;
  background: rgba(0,0,0,0.3);
  opacity: 0;
  transition: opacity 0.3s;
}

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

.play-icon {
  width: 50px;
  height: 50px;
  background: rgba(255,255,255,0.9);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 20px;
  color: var(--primary-color);
}

.video-info {
  padding: 16px;
}

.video-title {
  font-size: 16px;
  font-weight: 600;
  margin-bottom: 8px;
  overflow: hidden;
  text-overflow: ellipsis;
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  line-height: 1.4;
}

.video-meta {
  font-size: 13px;
  color: #888;
  margin-bottom: 8px;
}

.video-one-line {
  font-size: 14px;
  color: #666;
  line-height: 1.5;
  overflow: hidden;
  text-overflow: ellipsis;
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
}

.page-header {
  background: white;
  padding: 40px 20px;
  margin-bottom: 24px;
  border-bottom: 1px solid var(--border-color);
}

.page-title {
  font-size: 28px;
  font-weight: 700;
  color: var(--text-color);
}

.page {
  background: white;
  padding: 24px;
  border-radius: 8px;
  margin-bottom: 40px;
}

.top-list__items {
  list-style: none;
}

.top-list__item {
  display: flex;
  gap: 16px;
  padding: 20px;
  border-bottom: 1px solid var(--border-color);
  transition: background 0.3s;
}

.top-list__item:hover {
  background: #f9f9f9;
}

.rank-badge {
  flex-shrink: 0;
  width: 40px;
  height: 40px;
  background: var(--primary-color);
  color: white;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 18px;
  font-weight: 700;
}

.item-cover {
  flex-shrink: 0;
  width: 120px;
}

.item-cover img {
  width: 100%;
  height: 160px;
  object-fit: cover;
  border-radius: 4px;
}

.item-info {
  flex: 1;
}

.item-title {
  font-size: 18px;
  font-weight: 600;
  margin-bottom: 8px;
}

.item-title a {
  color: var(--text-color);
  text-decoration: none;
}

.item-title a:hover {
  color: var(--primary-color);
}

.item-meta {
  font-size: 14px;
  color: #888;
  margin-bottom: 8px;
}

.item-desc {
  font-size: 14px;
  color: #666;
  line-height: 1.6;
}

.group {
  margin-bottom: 40px;
}

.group__title {
  font-size: 22px;
  font-weight: 600;
  color: var(--text-color);
  margin-bottom: 20px;
  padding-bottom: 8px;
  border-bottom: 2px solid var(--primary-color);
}

.group__grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(260px, 1fr));
  gap: 24px;
}

.video-player-section {
  background: #000;
  padding: 40px 0;
}

.video-player {
  max-width: 900px;
  margin: 0 auto;
}

.video-player-inner {
  position: relative;
  width: 100%;
  padding-top: 56.25%;
  background: #1a1a1a;
  border-radius: 8px;
  overflow: hidden;
}

.player-play-btn {
  position: absolute;
  left: 50%;
  top: 50%;
  transform: translate(-50%, -50%);
  width: 80px;
  height: 80px;
  background: rgba(255,255,255,0.9);
  border: none;
  border-radius: 50%;
  cursor: pointer;
  transition: all 0.3s;
  display: flex;
  align-items: center;
  justify-content: center;
}

.player-play-btn:hover {
  background: white;
  transform: translate(-50%, -50%) scale(1.1);
}

.player-play-icon {
  font-size: 32px;
  color: var(--primary-color);
  margin-left: 4px;
}

.video-detail {
  background: white;
  padding: 40px;
  border-radius: 8px;
  margin-bottom: 40px;
}

.detail-header {
  margin-bottom: 32px;
}

.detail-title {
  font-size: 32px;
  font-weight: 700;
  color: var(--text-color);
  line-height: 1.3;
}

.detail-info {
  margin-bottom: 32px;
  padding: 24px;
  background: #f9f9f9;
  border-radius: 8px;
}

.module-title {
  font-size: 20px;
  font-weight: 600;
  color: var(--text-color);
  margin-bottom: 16px;
  padding-bottom: 8px;
  border-bottom: 2px solid var(--primary-color);
}

.info-list {
  display: grid;
  grid-template-columns: auto 1fr;
  gap: 12px 24px;
  font-size: 15px;
}

.info-list dt {
  font-weight: 600;
  color: #666;
}

.info-list dd {
  color: var(--text-color);
}

.detail-module {
  margin-bottom: 32px;
}

.module-content {
  font-size: 15px;
  line-height: 1.8;
  color: #555;
}

.module-content p {
  margin-bottom: 12px;
}

.tag-cloud {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}

.tag {
  display: inline-block;
  padding: 6px 16px;
  background: var(--primary-color);
  color: white;
  border-radius: 20px;
  font-size: 14px;
}

.related-section {
  margin-top: 40px;
  padding-top: 40px;
  border-top: 1px solid var(--border-color);
}

.related-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
  gap: 20px;
}

.video-card--related .video-cover {
  padding-top: 130%;
}

.site-footer {
  background: var(--text-color);
  color: white;
  padding: 30px 20px;
  text-align: center;
  margin-top: 40px;
}

.footer-content p {
  font-size: 14px;
  opacity: 0.8;
}

.back-to-top {
  position: fixed;
  bottom: 40px;
  right: 40px;
  width: 50px;
  height: 50px;
  background: var(--primary-color);
  color: white;
  border: none;
  border-radius: 50%;
  font-size: 24px;
  cursor: pointer;
  opacity: 0;
  visibility: hidden;
  transition: all 0.3s;
  z-index: 99;
}

.back-to-top.show {
  opacity: 1;
  visibility: visible;
}

.back-to-top:hover {
  background: var(--hover-color);
  transform: translateY(-4px);
}

@media (max-width: 768px) {
  .header-container {
    flex-direction: column;
    height: auto;
    padding: 12px 16px;
    gap: 12px;
  }

  .main-nav {
    width: 100%;
    justify-content: space-between;
    gap: 4px;
  }

  .main-nav a {
    padding: 6px 10px;
    font-size: 14px;
    flex: 1;
    text-align: center;
  }

  .hero-title {
    font-size: 24px;
  }

  .hero-desc {
    font-size: 14px;
  }

  .video-grid,
  .group__grid {
    grid-template-columns: repeat(2, 1fr);
    gap: 16px;
  }

  .related-grid {
    grid-template-columns: repeat(2, 1fr);
    gap: 16px;
  }

  .video-cover {
    padding-top: 145%;
  }

  .video-info {
    padding: 12px;
  }

  .video-title {
    font-size: 14px;
    -webkit-line-clamp: 2;
  }

  .video-one-line {
    font-size: 13px;
    -webkit-line-clamp: 2;
  }

  .top-list__item {
    flex-direction: column;
    padding: 16px;
  }

  .item-cover {
    width: 100%;
  }

  .item-cover img {
    width: 100%;
    height: auto;
    max-height: 300px;
  }

  .video-detail {
    padding: 20px;
  }

  .detail-title {
    font-size: 24px;
  }

  .back-to-top {
    bottom: 20px;
    right: 20px;
    width: 45px;
    height: 45px;
  }
}

@media (max-width: 480px) {
  .video-grid,
  .group__grid,
  .related-grid {
    grid-template-columns: 1fr;
  }

  .main-nav a {
    font-size: 13px;
    padding: 6px 8px;
  }
}