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

:root {
  --spacing-unit: 8px;
  --primary-color: #007bff;
  --bg-color: #ffffff;
  --text-color: #333333;
  --border-color: #e0e0e0;
  --hover-color: #f5f5f5;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
  line-height: 1.5;
  color: var(--text-color);
  background: var(--bg-color);
}

.ui-style-0 { --primary-color: #ff6b6b; --bg-color: #1a1a1a; --text-color: #ffffff; }
.ui-style-1 { --primary-color: #ff5722; --bg-color: #1a1a1a; --text-color: #ffffff; }
.ui-style-2 { --primary-color: #ff6b35; --bg-color: #ffffff; --text-color: #333333; }
.ui-style-3 { --primary-color: #ff0066; --bg-color: #ffffff; --text-color: #333333; }
.ui-style-4 { --primary-color: #e50914; --bg-color: #ffffff; --text-color: #333333; }
.ui-style-5 { --primary-color: #e50914; --bg-color: #141414; --text-color: #ffffff; }
.ui-style-6 { --primary-color: #1976d2; --bg-color: #0f1419; --text-color: #ffffff; }
.ui-style-7 { --primary-color: #2196f3; --bg-color: #0a1929; --text-color: #ffffff; }
.ui-style-8 { --primary-color: #00d363; --bg-color: #141414; --text-color: #ffffff; }
.ui-style-9 { --primary-color: #e5e5e5; --bg-color: #000000; --text-color: #ffffff; }
.ui-style-10 { --primary-color: #00c75a; --bg-color: #ffffff; --text-color: #333333; }
.ui-style-11 { --primary-color: #0099ff; --bg-color: #ffffff; --text-color: #333333; }
.ui-style-12 { --primary-color: #ff6700; --bg-color: #ffffff; --text-color: #333333; }
.ui-style-13 { --primary-color: #00a1d6; --bg-color: #ffffff; --text-color: #333333; }
.ui-style-14 { --primary-color: #1e50ae; --bg-color: #ffffff; --text-color: #333333; }

.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 calc(var(--spacing-unit) * 2);
}

.site-header {
  background: var(--bg-color);
  border-bottom: 1px solid var(--border-color);
  padding: calc(var(--spacing-unit) * 2) 0;
  position: sticky;
  top: 0;
  z-index: 100;
}

.site-header .container {
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: nowrap;
}

.site-logo {
  font-size: 24px;
  font-weight: 700;
  color: var(--primary-color);
  white-space: nowrap;
}

.site-nav {
  display: flex;
  gap: calc(var(--spacing-unit) * 2);
  white-space: nowrap;
  overflow: hidden;
}

.site-nav a {
  color: var(--text-color);
  text-decoration: none;
  padding: calc(var(--spacing-unit) * 1) calc(var(--spacing-unit) * 1.5);
  border-radius: 4px;
  transition: all 0.3s ease;
  white-space: nowrap;
}

.site-nav a:hover,
.site-nav a.active {
  background: var(--primary-color);
  color: #ffffff;
}

.site-main {
  min-height: calc(100vh - 200px);
}

.hero-section {
  padding: calc(var(--spacing-unit) * 8) 0 calc(var(--spacing-unit) * 6);
  text-align: center;
}

.page-title {
  font-size: 32px;
  font-weight: 700;
  margin-bottom: calc(var(--spacing-unit) * 3);
  line-height: 1.2;
}

.site-intro {
  max-width: 800px;
  margin: 0 auto;
  font-size: 16px;
  line-height: 1.5;
  opacity: 0.9;
}

.content-section {
  padding: calc(var(--spacing-unit) * 6) 0;
}

.section-title {
  font-size: 24px;
  font-weight: 700;
  margin-bottom: calc(var(--spacing-unit) * 4);
  padding-bottom: calc(var(--spacing-unit) * 2);
  border-bottom: 2px solid var(--primary-color);
}

.video-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: calc(var(--spacing-unit) * 3);
}

.video-card {
  background: var(--bg-color);
  border-radius: 8px;
  overflow: hidden;
  transition: transform 0.3s ease, box-shadow 0.3s ease;
  border: 1px solid var(--border-color);
}

.video-card:hover {
  transform: translateY(-4px);
  box-shadow: 0 8px 16px rgba(0, 0, 0, 0.1);
}

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

.play-icon {
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  width: 48px;
  height: 48px;
  background: rgba(0, 0, 0, 0.7);
  color: #ffffff;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 20px;
  opacity: 0;
  transition: opacity 0.3s ease;
}

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

.video-info {
  padding: calc(var(--spacing-unit) * 2);
}

.video-title {
  font-size: 16px;
  font-weight: 600;
  margin-bottom: calc(var(--spacing-unit) * 1);
  line-height: 1.2;
  overflow: hidden;
  text-overflow: ellipsis;
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
}

.video-meta {
  font-size: 14px;
  color: var(--text-color);
  opacity: 0.7;
  margin-bottom: calc(var(--spacing-unit) * 1);
}

.video-one-line {
  font-size: 14px;
  line-height: 1.5;
  opacity: 0.8;
  overflow: hidden;
  text-overflow: ellipsis;
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
}

.page-header-section {
  padding: calc(var(--spacing-unit) * 6) 0 calc(var(--spacing-unit) * 4);
  text-align: center;
  border-bottom: 1px solid var(--border-color);
}

.page-desc {
  margin-top: calc(var(--spacing-unit) * 2);
  font-size: 16px;
  opacity: 0.8;
}

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

.top-list__item {
  display: flex;
  align-items: flex-start;
  gap: calc(var(--spacing-unit) * 2);
  padding: calc(var(--spacing-unit) * 3);
  border-bottom: 1px solid var(--border-color);
  transition: background 0.3s ease;
}

.top-list__item:hover {
  background: var(--hover-color);
}

.top-rank {
  font-size: 24px;
  font-weight: 700;
  color: var(--primary-color);
  min-width: 40px;
  text-align: center;
}

.top-item__link {
  display: flex;
  gap: calc(var(--spacing-unit) * 2);
  text-decoration: none;
  color: inherit;
  flex: 1;
}

.video-cover--small {
  width: 160px;
  min-width: 160px;
  padding-top: 90px;
}

.video-player-section {
  padding: calc(var(--spacing-unit) * 4) 0;
}

.video-player {
  max-width: 1000px;
  margin: 0 auto;
}

.video-player-inner {
  position: relative;
  width: 100%;
  padding-top: 56.25%;
  background: #000000;
  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 ease;
  display: flex;
  align-items: center;
  justify-content: center;
}

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

.player-play-icon {
  font-size: 32px;
  color: #000000;
}

.video-detail-section {
  padding: calc(var(--spacing-unit) * 6) 0;
}

.video-detail-title {
  font-size: 36px;
  font-weight: 700;
  margin-bottom: calc(var(--spacing-unit) * 4);
  line-height: 1.2;
}

.video-basic-info {
  background: var(--hover-color);
  padding: calc(var(--spacing-unit) * 3);
  border-radius: 8px;
  margin-bottom: calc(var(--spacing-unit) * 6);
}

.info-title {
  font-size: 18px;
  font-weight: 600;
  margin-bottom: calc(var(--spacing-unit) * 2);
}

.info-list {
  display: grid;
  grid-template-columns: 80px 1fr;
  gap: calc(var(--spacing-unit) * 2);
  font-size: 15px;
}

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

.detail-module {
  margin-bottom: calc(var(--spacing-unit) * 6);
}

.module-title {
  font-size: 22px;
  font-weight: 700;
  margin-bottom: calc(var(--spacing-unit) * 3);
  padding-bottom: calc(var(--spacing-unit) * 2);
  border-bottom: 2px solid var(--primary-color);
}

.module-content {
  font-size: 16px;
  line-height: 1.5;
}

.module-content p {
  margin-bottom: calc(var(--spacing-unit) * 2);
}

.tag-cloud {
  display: flex;
  flex-wrap: wrap;
  gap: calc(var(--spacing-unit) * 2);
}

.tag {
  display: inline-block;
  padding: calc(var(--spacing-unit) * 1) calc(var(--spacing-unit) * 2);
  background: var(--primary-color);
  color: #ffffff;
  border-radius: 20px;
  font-size: 14px;
}

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

.video-card--related .video-cover {
  padding-top: 66%;
}

.site-footer {
  background: var(--bg-color);
  border-top: 1px solid var(--border-color);
  padding: calc(var(--spacing-unit) * 4) 0;
  text-align: center;
  margin-top: calc(var(--spacing-unit) * 8);
}

.site-footer p {
  font-size: 14px;
  opacity: 0.7;
}

@media (max-width: 768px) {
  .site-header .container {
    flex-direction: column;
    gap: calc(var(--spacing-unit) * 2);
  }

  .site-nav {
    gap: calc(var(--spacing-unit) * 1);
    font-size: 14px;
  }

  .site-nav a {
    padding: calc(var(--spacing-unit) * 0.5) calc(var(--spacing-unit) * 1);
  }

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

  .video-grid {
    grid-template-columns: repeat(auto-fill, minmax(160px, 1fr));
    gap: calc(var(--spacing-unit) * 2);
  }

  .video-cover {
    padding-top: 56.25%;
  }

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

  .video-detail-title {
    font-size: 28px;
  }

  .top-item__link {
    flex-direction: column;
  }

  .video-cover--small {
    width: 100%;
    padding-top: 56.25%;
  }
}

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

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