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

body {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'PingFang SC', 'Hiragino Sans GB', 'Microsoft YaHei', sans-serif;
  line-height: 1.6;
  color: #333;
  background: #fff;
}

.ui-style-13 {
  --primary-color: #00A1D6;
  --secondary-color: #FB7299;
  --bg-color: #fff;
  --text-color: #333;
  --border-color: #e1e8ed;
}

.ui-style-13 a {
  color: var(--primary-color);
  text-decoration: none;
  transition: color 0.2s ease;
}

.ui-style-13 a:hover {
  color: var(--secondary-color);
}

.site-header {
  background: #fff;
  border-bottom: 1px solid var(--border-color);
  padding: 1rem 0;
  position: sticky;
  top: 0;
  z-index: 100;
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.05);
}

.header-container {
  max-width: 1400px;
  margin: 0 auto;
  padding: 0 2rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 2rem;
}

.site-logo a {
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--primary-color);
}

.site-nav {
  display: flex;
  gap: 0.5rem;
  flex-wrap: nowrap;
  overflow-x: auto;
  -webkit-overflow-scrolling: touch;
  scrollbar-width: none;
}

.site-nav::-webkit-scrollbar {
  display: none;
}

.nav-link {
  padding: 0.5rem 1rem;
  border-radius: 20px;
  white-space: nowrap;
  font-size: 0.9rem;
  transition: all 0.2s ease;
}

.nav-link:hover,
.nav-link.active {
  background: var(--primary-color);
  color: #fff;
}

.site-main {
  max-width: 1400px;
  margin: 0 auto;
  padding: 2rem;
}

.hero-section {
  background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
  color: #fff;
  padding: 3rem 2rem;
  border-radius: 16px;
  margin-bottom: 2rem;
}

.hero-title {
  font-size: 2rem;
  margin-bottom: 1rem;
  line-height: 1.3;
}

.hero-desc {
  font-size: 1rem;
  line-height: 1.8;
  opacity: 0.95;
}

.video-section {
  margin-bottom: 3rem;
}

.section-header {
  margin-bottom: 1.5rem;
  padding-bottom: 0.75rem;
  border-bottom: 2px solid var(--primary-color);
}

.section-title {
  font-size: 1.5rem;
  color: var(--text-color);
}

.video-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 1.5rem;
}

.video-grid.masonry {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  grid-auto-rows: 10px;
  gap: 1.5rem;
}

.video-grid.masonry .video-card {
  grid-row-end: span var(--row-span, 30);
}

.video-card {
  background: #fff;
  border-radius: 12px;
  overflow: hidden;
  box-shadow: 0 2px 12px rgba(0, 0, 0, 0.08);
  transition: all 0.3s ease;
}

.video-card:hover {
  transform: translateY(-4px);
  box-shadow: 0 8px 24px rgba(0, 0, 0, 0.15);
}

.video-card__link {
  display: block;
  color: inherit;
}

.video-cover {
  position: relative;
  width: 100%;
  padding-top: 56.25%;
  background: #f0f0f0;
  overflow: hidden;
}

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

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

.video-info {
  padding: 1rem;
}

.video-title {
  font-size: 1.1rem;
  margin-bottom: 0.5rem;
  color: var(--text-color);
  font-weight: 600;
  overflow: hidden;
  text-overflow: ellipsis;
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
}

.video-one-line {
  font-size: 0.9rem;
  color: #666;
  line-height: 1.5;
  overflow: hidden;
  text-overflow: ellipsis;
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
}

.page-header {
  margin-bottom: 2rem;
  padding-bottom: 1rem;
  border-bottom: 2px solid var(--primary-color);
}

.page-header h1 {
  font-size: 2rem;
  margin-bottom: 0.5rem;
  color: var(--text-color);
}

.page-desc {
  font-size: 1rem;
  color: #666;
  line-height: 1.6;
}

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

.top-item {
  counter-increment: top-counter;
  margin-bottom: 1.5rem;
  background: #fff;
  border-radius: 12px;
  box-shadow: 0 2px 12px rgba(0, 0, 0, 0.08);
  overflow: hidden;
  transition: all 0.3s ease;
}

.top-item:hover {
  transform: translateX(8px);
  box-shadow: 0 4px 20px rgba(0, 0, 0, 0.12);
}

.top-item__link {
  display: flex;
  align-items: center;
  gap: 1.5rem;
  padding: 1rem;
  color: inherit;
}

.top-rank {
  font-size: 2rem;
  font-weight: 700;
  color: var(--primary-color);
  min-width: 60px;
  text-align: center;
}

.top-item:nth-child(1) .top-rank {
  color: #FFD700;
}

.top-item:nth-child(2) .top-rank {
  color: #C0C0C0;
}

.top-item:nth-child(3) .top-rank {
  color: #CD7F32;
}

.top-cover {
  width: 120px;
  height: 180px;
  object-fit: cover;
  border-radius: 8px;
}

.top-info {
  flex: 1;
}

.top-info h3 {
  font-size: 1.2rem;
  margin-bottom: 0.5rem;
  color: var(--text-color);
}

.top-info p {
  font-size: 0.9rem;
  color: #666;
  margin-bottom: 0.5rem;
  line-height: 1.5;
}

.top-meta {
  font-size: 0.85rem;
  color: #999;
}

.group {
  margin-bottom: 3rem;
}

.group__title {
  font-size: 1.5rem;
  margin-bottom: 1rem;
  color: var(--primary-color);
  padding-bottom: 0.5rem;
  border-bottom: 2px solid var(--border-color);
}

.group__grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 1.5rem;
}

.layout-with-sidebar {
  display: grid;
  grid-template-columns: 250px 1fr;
  gap: 2rem;
}

.layout__side--filters {
  background: #f8f9fa;
  padding: 1.5rem;
  border-radius: 12px;
  height: fit-content;
  position: sticky;
  top: 100px;
}

.layout__side--filters h2 {
  font-size: 1.2rem;
  margin-bottom: 1rem;
  color: var(--text-color);
}

.layout__side--filters p {
  font-size: 0.9rem;
  color: #666;
  line-height: 1.6;
}

.video-player-section {
  margin-bottom: 2rem;
}

.video-player {
  max-width: 1200px;
  margin: 0 auto;
}

.video-player-inner {
  position: relative;
  width: 100%;
  padding-top: 56.25%;
  background: #000;
  border-radius: 12px;
  overflow: hidden;
}

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

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

.player-play-icon {
  font-size: 2rem;
  color: var(--primary-color);
  margin-left: 4px;
}

.detail-header {
  margin-bottom: 2rem;
}

.detail-header h1 {
  font-size: 2rem;
  color: var(--text-color);
}

.detail-info {
  background: #f8f9fa;
  padding: 1.5rem;
  border-radius: 12px;
  margin-bottom: 2rem;
}

.detail-info h2 {
  font-size: 1.3rem;
  margin-bottom: 1rem;
  color: var(--text-color);
}

.info-list {
  display: grid;
  grid-template-columns: 100px 1fr;
  gap: 0.75rem;
  font-size: 0.95rem;
}

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

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

.detail-module {
  margin-bottom: 2rem;
  padding: 1.5rem;
  background: #fff;
  border-radius: 12px;
  border: 1px solid var(--border-color);
}

.detail-module h2 {
  font-size: 1.3rem;
  margin-bottom: 1rem;
  color: var(--primary-color);
}

.module-content {
  font-size: 1rem;
  color: var(--text-color);
  line-height: 1.8;
}

.tags-cloud {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
}

.tag {
  display: inline-block;
  padding: 0.4rem 0.8rem;
  background: var(--primary-color);
  color: #fff;
  border-radius: 20px;
  font-size: 0.85rem;
}

.related-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(250px, 1fr));
  gap: 1.5rem;
}

.site-footer {
  background: #f8f9fa;
  padding: 2rem 0;
  margin-top: 4rem;
  border-top: 1px solid var(--border-color);
}

.footer-container {
  max-width: 1400px;
  margin: 0 auto;
  padding: 0 2rem;
  text-align: center;
  color: #666;
  font-size: 0.9rem;
}

@media (max-width: 768px) {
  .header-container {
    flex-direction: column;
    gap: 1rem;
    padding: 0 1rem;
  }

  .site-nav {
    width: 100%;
    overflow-x: auto;
    padding: 0.5rem 0;
  }

  .nav-link {
    font-size: 0.85rem;
    padding: 0.4rem 0.8rem;
  }

  .site-main {
    padding: 1rem;
  }

  .hero-section {
    padding: 2rem 1.5rem;
  }

  .hero-title {
    font-size: 1.5rem;
  }

  .hero-desc {
    font-size: 0.9rem;
  }

  .video-grid,
  .video-grid.masonry {
    grid-template-columns: repeat(auto-fill, minmax(150px, 1fr));
    gap: 1rem;
    grid-auto-rows: auto;
  }

  .video-grid.masonry .video-card {
    grid-row-end: auto;
  }

  .video-cover {
    padding-top: 50%;
  }

  .video-info {
    padding: 0.75rem;
  }

  .video-title {
    font-size: 0.95rem;
  }

  .video-one-line {
    font-size: 0.8rem;
    -webkit-line-clamp: 1;
  }

  .layout-with-sidebar {
    grid-template-columns: 1fr;
  }

  .layout__side--filters {
    position: static;
  }

  .top-item__link {
    flex-direction: column;
    text-align: center;
  }

  .top-cover {
    width: 100%;
    height: auto;
    max-width: 200px;
  }

  .top-rank {
    min-width: auto;
  }

  .group__grid {
    grid-template-columns: repeat(auto-fill, minmax(150px, 1fr));
    gap: 1rem;
  }

  .related-grid {
    grid-template-columns: repeat(auto-fill, minmax(150px, 1fr));
    gap: 1rem;
  }

  .info-list {
    grid-template-columns: 80px 1fr;
    gap: 0.5rem;
    font-size: 0.85rem;
  }

  .player-play-btn {
    width: 60px;
    height: 60px;
  }

  .player-play-icon {
    font-size: 1.5rem;
  }
}

@media (min-width: 769px) and (max-width: 1024px) {
  .video-grid,
  .video-grid.masonry {
    grid-template-columns: repeat(auto-fill, minmax(220px, 1fr));
  }
}

.back-to-top {
  position: fixed;
  bottom: 2rem;
  right: 2rem;
  width: 50px;
  height: 50px;
  border-radius: 50%;
  background: var(--primary-color);
  color: #fff;
  border: none;
  cursor: pointer;
  display: none;
  align-items: center;
  justify-content: center;
  font-size: 1.5rem;
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.15);
  transition: all 0.3s ease;
  z-index: 99;
}

.back-to-top.show {
  display: flex;
}

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