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

:root {
  --spacing: 8px;
  --primary-color: #1a1a1a;
  --text-color: #333;
  --bg-color: #fff;
  --border-color: #e0e0e0;
  --hover-color: #f5f5f5;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  line-height: 1.6;
  color: var(--text-color);
  background-color: var(--bg-color);
}

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

.site-header {
  background: var(--bg-color);
  border-bottom: 1px solid var(--border-color);
  padding: calc(var(--spacing) * 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 a {
  font-size: 24px;
  font-weight: 700;
  color: var(--primary-color);
  text-decoration: none;
}

.site-nav {
  display: flex;
  gap: calc(var(--spacing) * 3);
  align-items: center;
  white-space: nowrap;
  overflow: visible;
}

.site-nav a {
  color: var(--text-color);
  text-decoration: none;
  font-size: 15px;
  transition: color 0.3s;
}

.site-nav a:hover,
.site-nav a.active {
  color: var(--primary-color);
  font-weight: 600;
}

.hero-section {
  background: linear-gradient(135deg, #f5f7fa 0%, #c3cfe2 100%);
  padding: calc(var(--spacing) * 8) 0;
  text-align: center;
}

.hero-title {
  font-size: 32px;
  font-weight: 700;
  margin-bottom: calc(var(--spacing) * 3);
  line-height: 1.3;
}

.hero-desc {
  font-size: 16px;
  line-height: 1.8;
  max-width: 900px;
  margin: 0 auto;
  color: #555;
}

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

.section-title {
  font-size: 26px;
  font-weight: 700;
  margin-bottom: calc(var(--spacing) * 4);
  padding-left: calc(var(--spacing) * 2);
  border-left: 4px solid var(--primary-color);
}

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

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

.video-card:hover {
  transform: translateY(-4px);
  box-shadow: 0 8px 24px rgba(0,0,0,0.1);
}

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

.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;
}

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

.video-title {
  font-size: 18px;
  font-weight: 600;
  margin-bottom: calc(var(--spacing));
  overflow: hidden;
  text-overflow: ellipsis;
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
}

.video-one-line {
  font-size: 14px;
  color: #666;
  margin-bottom: calc(var(--spacing));
  overflow: hidden;
  text-overflow: ellipsis;
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
}

.video-meta {
  display: flex;
  gap: calc(var(--spacing) * 2);
  font-size: 13px;
  color: #999;
}

.page-header {
  padding: calc(var(--spacing) * 6) 0 calc(var(--spacing) * 4) 0;
}

.page-header h1 {
  font-size: 32px;
  font-weight: 700;
  margin-bottom: calc(var(--spacing) * 2);
}

.page-desc {
  font-size: 16px;
  color: #666;
  line-height: 1.8;
}

.page--grid,
.page--with-sidebar,
.page--top,
.page--grouped {
  padding: calc(var(--spacing) * 4) 0;
}

.page--with-sidebar .container {
  display: grid;
  grid-template-columns: 240px 1fr;
  gap: calc(var(--spacing) * 4);
}

.layout__side--filters {
  background: var(--hover-color);
  padding: calc(var(--spacing) * 3);
  border-radius: 8px;
  height: fit-content;
  position: sticky;
  top: 100px;
}

.layout__side--filters h3 {
  font-size: 18px;
  margin-bottom: calc(var(--spacing) * 2);
}

.layout__side--filters p {
  font-size: 14px;
  color: #666;
}

.top-list__items {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: calc(var(--spacing) * 3);
}

.top-item {
  background: var(--bg-color);
  border: 1px solid var(--border-color);
  border-radius: 8px;
  overflow: hidden;
  transition: box-shadow 0.3s;
}

.top-item:hover {
  box-shadow: 0 4px 12px rgba(0,0,0,0.1);
}

.top-item__link {
  display: flex;
  align-items: center;
  gap: calc(var(--spacing) * 2);
  padding: calc(var(--spacing) * 2);
  text-decoration: none;
  color: inherit;
}

.top-rank {
  font-size: 28px;
  font-weight: 700;
  color: var(--primary-color);
  min-width: 50px;
  text-align: center;
}

.top-item .video-cover {
  width: 160px;
  padding-top: 90px;
  flex-shrink: 0;
}

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

.group {
  margin-bottom: calc(var(--spacing) * 6);
}

.group__title {
  font-size: 24px;
  font-weight: 700;
  margin-bottom: calc(var(--spacing) * 3);
  padding-left: calc(var(--spacing) * 2);
  border-left: 4px solid var(--primary-color);
}

.group__grid {
  margin-top: calc(var(--spacing) * 3);
}

.video-player-section {
  background: #000;
  padding: calc(var(--spacing) * 4) 0;
}

.video-player {
  max-width: 1000px;
  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%);
  background: rgba(255,255,255,0.9);
  border: none;
  width: 80px;
  height: 80px;
  border-radius: 50%;
  cursor: pointer;
  transition: all 0.3s;
  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: 32px;
  color: #000;
  margin-left: 4px;
}

.video-header {
  padding: calc(var(--spacing) * 6) 0 calc(var(--spacing) * 3) 0;
}

.video-header h1 {
  font-size: 36px;
  font-weight: 700;
}

.video-basic-info {
  padding: calc(var(--spacing) * 4) 0;
  background: var(--hover-color);
}

.video-basic-info h2 {
  font-size: 22px;
  font-weight: 700;
  margin-bottom: calc(var(--spacing) * 3);
}

.info-list {
  display: grid;
  grid-template-columns: 100px 1fr;
  gap: calc(var(--spacing) * 2);
  max-width: 800px;
}

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

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

.content-module {
  padding: calc(var(--spacing) * 5) 0;
  border-bottom: 1px solid var(--border-color);
}

.content-module h2 {
  font-size: 24px;
  font-weight: 700;
  margin-bottom: calc(var(--spacing) * 3);
}

.module-content {
  font-size: 16px;
  line-height: 1.8;
  color: #555;
  max-width: 900px;
}

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

.tag-item {
  display: inline-block;
  background: var(--hover-color);
  padding: calc(var(--spacing)) calc(var(--spacing) * 2);
  margin: calc(var(--spacing)) calc(var(--spacing)) 0 0;
  border-radius: 4px;
  font-size: 14px;
}

.related-videos {
  padding: calc(var(--spacing) * 6) 0;
}

.related-videos h2 {
  font-size: 26px;
  font-weight: 700;
  margin-bottom: calc(var(--spacing) * 4);
}

.video-grid--related {
  grid-template-columns: repeat(auto-fill, minmax(240px, 1fr));
}

.site-footer {
  background: var(--primary-color);
  color: #fff;
  padding: calc(var(--spacing) * 4) 0;
  text-align: center;
  margin-top: calc(var(--spacing) * 8);
}

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

.ui-style-0 {
  --primary-color: #1a1a1a;
  --text-color: #333;
  --bg-color: #fff;
  --border-color: #e0e0e0;
  --hover-color: #f5f5f5;
}

.ui-style-1 {
  --primary-color: #ff6b35;
  --text-color: #2c3e50;
  --bg-color: #fff;
  --border-color: #ddd;
  --hover-color: #fff5f2;
}

.ui-style-2 {
  --primary-color: #e74c3c;
  --text-color: #2c3e50;
  --bg-color: #fff;
  --border-color: #ecf0f1;
  --hover-color: #fef5f4;
}

.ui-style-3 {
  --primary-color: #e63946;
  --text-color: #1d3557;
  --bg-color: #fff;
  --border-color: #e0e0e0;
  --hover-color: #fef1f2;
}

.ui-style-4 {
  --primary-color: #d32f2f;
  --text-color: #212121;
  --bg-color: #fff;
  --border-color: #e0e0e0;
  --hover-color: #ffebee;
}

.ui-style-5 {
  --primary-color: #e50914;
  --text-color: #fff;
  --bg-color: #141414;
  --border-color: #333;
  --hover-color: #1f1f1f;
}

.ui-style-5 .video-card,
.ui-style-5 .top-item {
  background: #1f1f1f;
  border-color: #333;
}

.ui-style-6 {
  --primary-color: #0063e5;
  --text-color: #f9f9f9;
  --bg-color: #1a1d29;
  --border-color: #2d3142;
  --hover-color: #2d3142;
}

.ui-style-6 .video-card,
.ui-style-6 .top-item {
  background: #2d3142;
  border-color: #3a3f5c;
}

.ui-style-7 {
  --primary-color: #0084ff;
  --text-color: #cacaca;
  --bg-color: #0f111a;
  --border-color: #1a1d2e;
  --hover-color: #1a1d2e;
}

.ui-style-7 .video-card,
.ui-style-7 .top-item {
  background: #1a1d2e;
  border-color: #252a41;
}

.ui-style-8 {
  --primary-color: #00b14f;
  --text-color: #e0e0e0;
  --bg-color: #1a1a1a;
  --border-color: #2a2a2a;
  --hover-color: #242424;
}

.ui-style-8 .video-card,
.ui-style-8 .top-item {
  background: #242424;
  border-color: #2a2a2a;
}

.ui-style-9 {
  --primary-color: #fff;
  --text-color: #fff;
  --bg-color: #000;
  --border-color: #1a1a1a;
  --hover-color: #0d0d0d;
}

.ui-style-9 .video-card,
.ui-style-9 .top-item {
  background: #0d0d0d;
  border-color: #1a1a1a;
}

.ui-style-10 {
  --primary-color: #00e676;
  --text-color: #212121;
  --bg-color: #f5f5f5;
  --border-color: #e0e0e0;
  --hover-color: #e8f5e9;
}

.ui-style-11 {
  --primary-color: #0099ff;
  --text-color: #333;
  --bg-color: #fafafa;
  --border-color: #e5e5e5;
  --hover-color: #f0f8ff;
}

.ui-style-12 {
  --primary-color: #ff6700;
  --text-color: #333;
  --bg-color: #fff;
  --border-color: #e0e0e0;
  --hover-color: #fff5f0;
}

.ui-style-13 {
  --primary-color: #00a1d6;
  --text-color: #222;
  --bg-color: #fff;
  --border-color: #e3e5e7;
  --hover-color: #f4f5f7;
}

.ui-style-14 {
  --primary-color: #003a8c;
  --text-color: #333;
  --bg-color: #fff;
  --border-color: #d9d9d9;
  --hover-color: #f0f5ff;
}

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

  .site-nav {
    gap: calc(var(--spacing) * 2);
    font-size: 14px;
  }

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

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

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

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

  .video-title {
    font-size: 15px;
  }

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

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

  .layout__side--filters {
    position: static;
  }

  .top-item__link {
    flex-direction: column;
    align-items: flex-start;
  }

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

  .video-header h1 {
    font-size: 24px;
  }

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

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

@media (max-width: 480px) {
  .site-nav {
    gap: calc(var(--spacing));
    font-size: 13px;
  }
}