* {
  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: #000;
}

body.ui-style-9 {
  background: linear-gradient(to bottom, #0a0a0a 0%, #1a1a1a 100%);
  color: #ffffff;
}

.site-nav {
  background: rgba(0, 0, 0, 0.95);
  position: sticky;
  top: 0;
  z-index: 1000;
  border-bottom: 1px solid rgba(255, 255, 255, 0.1);
  backdrop-filter: blur(10px);
}

.nav-container {
  max-width: 1400px;
  margin: 0 auto;
  padding: 0 20px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 64px;
}

.site-logo {
  font-size: 24px;
  font-weight: 700;
  color: #fff;
  text-decoration: none;
  letter-spacing: 1px;
}

.nav-menu {
  list-style: none;
  display: flex;
  gap: 32px;
}

.nav-menu a {
  color: rgba(255, 255, 255, 0.8);
  text-decoration: none;
  font-size: 15px;
  transition: color 0.3s;
  white-space: nowrap;
}

.nav-menu a:hover {
  color: #fff;
}

.home-main,
.list-main,
.detail-main {
  max-width: 1400px;
  margin: 0 auto;
  padding: 40px 20px;
}

.hero-section {
  text-align: center;
  padding: 60px 20px;
  background: linear-gradient(135deg, rgba(255, 255, 255, 0.05) 0%, rgba(255, 255, 255, 0.02) 100%);
  border-radius: 16px;
  margin-bottom: 60px;
}

.hero-title {
  font-size: 36px;
  font-weight: 700;
  margin-bottom: 20px;
  color: #fff;
  line-height: 1.3;
}

.hero-desc {
  font-size: 16px;
  color: rgba(255, 255, 255, 0.7);
  max-width: 800px;
  margin: 0 auto;
  line-height: 1.8;
}

.content-section {
  margin-bottom: 60px;
}

.section-title {
  font-size: 28px;
  font-weight: 600;
  margin-bottom: 30px;
  color: #fff;
  padding-bottom: 12px;
  border-bottom: 2px solid rgba(255, 255, 255, 0.1);
}

.video-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 24px;
}

.video-grid.masonry {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 24px;
  grid-auto-flow: dense;
}

.video-card {
  background: rgba(255, 255, 255, 0.05);
  border-radius: 12px;
  overflow: hidden;
  transition: transform 0.3s, box-shadow 0.3s;
}

.video-card:hover {
  transform: translateY(-4px);
  box-shadow: 0 12px 24px rgba(0, 0, 0, 0.3);
}

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

.video-cover {
  position: relative;
  width: 100%;
  padding-top: 140%;
  background: #1a1a1a;
  overflow: hidden;
}

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

.play-icon {
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  width: 48px;
  height: 48px;
  background: rgba(255, 255, 255, 0.9);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 20px;
  opacity: 0;
  transition: opacity 0.3s;
}

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

.video-info {
  padding: 16px;
}

.video-title {
  font-size: 16px;
  font-weight: 600;
  margin-bottom: 8px;
  color: #fff;
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

.video-meta {
  font-size: 13px;
  color: rgba(255, 255, 255, 0.5);
  margin-bottom: 8px;
}

.video-one-line {
  font-size: 14px;
  color: rgba(255, 255, 255, 0.7);
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
  line-height: 1.5;
}

.page-header {
  margin-bottom: 40px;
  text-align: center;
}

.page-header h1 {
  font-size: 36px;
  font-weight: 700;
  margin-bottom: 12px;
  color: #fff;
}

.page-header p {
  font-size: 16px;
  color: rgba(255, 255, 255, 0.6);
}

.top-list__items {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 20px;
}

.top-item {
  display: flex;
  align-items: center;
  gap: 20px;
  background: rgba(255, 255, 255, 0.05);
  border-radius: 12px;
  padding: 16px;
  transition: background 0.3s;
}

.top-item:hover {
  background: rgba(255, 255, 255, 0.08);
}

.top-rank {
  font-size: 32px;
  font-weight: 700;
  color: rgba(255, 255, 255, 0.3);
  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-item .video-cover {
  width: 120px;
  height: 160px;
  padding-top: 0;
  flex-shrink: 0;
  border-radius: 8px;
}

.top-item .video-cover img {
  position: static;
  width: 100%;
  height: 100%;
}

.top-item .video-info {
  flex: 1;
  padding: 0;
}

.top-item .video-title {
  font-size: 18px;
  margin-bottom: 8px;
}

.top-item .video-title a {
  color: #fff;
  text-decoration: none;
}

.top-item .video-title a:hover {
  text-decoration: underline;
}

.group {
  margin-bottom: 50px;
}

.group__title {
  font-size: 24px;
  font-weight: 600;
  margin-bottom: 20px;
  color: #fff;
  padding-bottom: 8px;
  border-bottom: 2px solid rgba(255, 255, 255, 0.1);
}

.group__grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 24px;
}

.video-player-section {
  margin-bottom: 40px;
}

.video-player {
  max-width: 1000px;
  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;
  background: rgba(255, 255, 255, 0.95);
  border: none;
  border-radius: 50%;
  cursor: pointer;
  transition: transform 0.3s, background 0.3s;
}

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

.player-play-icon {
  font-size: 32px;
  color: #000;
}

.detail-header {
  margin-bottom: 30px;
}

.detail-header h1 {
  font-size: 36px;
  font-weight: 700;
  color: #fff;
  line-height: 1.3;
}

.detail-section {
  margin-bottom: 40px;
  background: rgba(255, 255, 255, 0.05);
  border-radius: 12px;
  padding: 30px;
}

.detail-section h2 {
  font-size: 24px;
  font-weight: 600;
  margin-bottom: 16px;
  color: #fff;
}

.detail-section p {
  font-size: 15px;
  line-height: 1.8;
  color: rgba(255, 255, 255, 0.8);
}

.info-list {
  display: grid;
  grid-template-columns: 100px 1fr;
  gap: 12px 20px;
  font-size: 15px;
}

.info-list dt {
  color: rgba(255, 255, 255, 0.5);
  font-weight: 500;
}

.info-list dd {
  color: rgba(255, 255, 255, 0.9);
}

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

.tag {
  display: inline-block;
  padding: 6px 16px;
  background: rgba(255, 255, 255, 0.1);
  border-radius: 20px;
  font-size: 14px;
  color: rgba(255, 255, 255, 0.9);
}

.related-section .video-grid {
  grid-template-columns: repeat(auto-fill, minmax(220px, 1fr));
}

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

.site-footer {
  background: rgba(0, 0, 0, 0.8);
  color: rgba(255, 255, 255, 0.5);
  text-align: center;
  padding: 40px 20px;
  margin-top: 60px;
  border-top: 1px solid rgba(255, 255, 255, 0.1);
}

.site-footer p {
  font-size: 14px;
}

#back-to-top {
  position: fixed;
  bottom: 40px;
  right: 40px;
  width: 48px;
  height: 48px;
  background: rgba(255, 255, 255, 0.9);
  border: none;
  border-radius: 50%;
  cursor: pointer;
  opacity: 0;
  visibility: hidden;
  transition: opacity 0.3s, visibility 0.3s, transform 0.3s;
  z-index: 999;
  font-size: 20px;
  color: #000;
}

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

#back-to-top:hover {
  transform: translateY(-4px);
}

@media (max-width: 768px) {
  .nav-menu {
    gap: 16px;
    font-size: 13px;
  }

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

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

  .section-title {
    font-size: 22px;
  }

  .video-grid,
  .video-grid.masonry,
  .group__grid {
    grid-template-columns: repeat(auto-fill, minmax(160px, 1fr));
    gap: 16px;
  }

  .video-cover {
    padding-top: 150%;
  }

  .video-info {
    padding: 12px;
  }

  .video-title {
    font-size: 14px;
  }

  .video-one-line {
    font-size: 12px;
    -webkit-line-clamp: 2;
  }

  .page-header h1 {
    font-size: 28px;
  }

  .top-item {
    flex-wrap: wrap;
  }

  .top-rank {
    min-width: 40px;
    font-size: 24px;
  }

  .top-item .video-cover {
    width: 80px;
    height: 110px;
  }

  .detail-header h1 {
    font-size: 28px;
  }

  .detail-section {
    padding: 20px;
  }

  .detail-section h2 {
    font-size: 20px;
  }

  .related-section .video-grid {
    grid-template-columns: repeat(auto-fill, minmax(140px, 1fr));
  }

  #back-to-top {
    bottom: 20px;
    right: 20px;
    width: 40px;
    height: 40px;
  }
}

@media (max-width: 480px) {
  .nav-container {
    padding: 0 12px;
    height: 56px;
  }

  .site-logo {
    font-size: 18px;
  }

  .nav-menu {
    gap: 12px;
    font-size: 12px;
  }

  .hero-section {
    padding: 40px 16px;
  }

  .video-grid,
  .video-grid.masonry,
  .group__grid {
    grid-template-columns: repeat(2, 1fr);
    gap: 12px;
  }

  .info-list {
    grid-template-columns: 80px 1fr;
    gap: 8px 12px;
  }
}