* {
  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;
}

body.ui-style-5 {
  background: #141414;
  color: #fff;
}

.container {
  max-width: 1400px;
  margin: 0 auto;
  padding: 0 20px;
}

header {
  background: #000;
  color: #fff;
  padding: 16px 0;
  position: sticky;
  top: 0;
  z-index: 1000;
}

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

.logo {
  font-size: 24px;
  font-weight: 700;
  color: #e50914;
  text-decoration: none;
}

nav ul {
  display: flex;
  list-style: none;
  gap: 8px;
  margin: 0;
}

nav a {
  color: #fff;
  text-decoration: none;
  padding: 8px 12px;
  border-radius: 4px;
  transition: background 0.2s;
  white-space: nowrap;
  font-size: 14px;
}

nav a:hover,
nav a.active {
  background: rgba(255,255,255,0.1);
}

main {
  min-height: calc(100vh - 200px);
  padding: 40px 0;
}

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

.page-header h1 {
  font-size: 32px;
  margin-bottom: 12px;
  color: #fff;
}

.page-intro {
  font-size: 16px;
  color: #aaa;
  max-width: 900px;
  line-height: 1.8;
}

.group {
  margin-bottom: 48px;
}

.group h2 {
  font-size: 24px;
  margin-bottom: 20px;
  color: #fff;
  padding-left: 12px;
  border-left: 4px solid #e50914;
}

.group__grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(220px, 1fr));
  gap: 24px;
}

.video-card {
  background: #1a1a1a;
  border-radius: 8px;
  overflow: hidden;
  transition: transform 0.2s, box-shadow 0.2s;
  cursor: pointer;
}

.video-card:hover {
  transform: translateY(-4px);
  box-shadow: 0 8px 24px rgba(0,0,0,0.4);
}

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

.video-cover {
  position: relative;
  width: 100%;
  padding-top: 140%;
  overflow: hidden;
  background: #000;
}

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

.video-info {
  padding: 16px;
}

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

.video-one-line,
.video-meta {
  font-size: 14px;
  color: #888;
  overflow: hidden;
  text-overflow: ellipsis;
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
}

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

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

.video-player-inner {
  position: relative;
  width: 100%;
  padding-top: 56.25%;
  background: #000;
  border-radius: 8px;
  overflow: hidden;
}

.player-play-btn {
  position: absolute;
  left: 50%;
  top: 50%;
  transform: translate(-50%, -50%);
  width: 80px;
  height: 80px;
  background: rgba(229,9,20,0.9);
  border: none;
  border-radius: 50%;
  cursor: pointer;
  transition: transform 0.2s;
}

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

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

.detail-header {
  max-width: 1000px;
  margin: 0 auto 32px;
}

.detail-header h1 {
  font-size: 36px;
  margin-bottom: 16px;
  color: #fff;
}

.detail-section {
  max-width: 1000px;
  margin: 0 auto 32px;
  background: #1a1a1a;
  padding: 24px;
  border-radius: 8px;
}

.detail-section h2 {
  font-size: 22px;
  margin-bottom: 16px;
  color: #fff;
  padding-bottom: 12px;
  border-bottom: 1px solid #333;
}

.detail-section p {
  color: #ccc;
  line-height: 1.8;
  margin-bottom: 12px;
}

.info-grid {
  display: grid;
  grid-template-columns: 100px 1fr;
  gap: 12px;
  color: #ccc;
}

.info-grid dt {
  color: #888;
}

.info-grid dd {
  color: #fff;
}

.tag-list {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-top: 8px;
}

.tag {
  background: #333;
  color: #fff;
  padding: 4px 12px;
  border-radius: 16px;
  font-size: 14px;
}

.related-section {
  max-width: 1400px;
  margin: 0 auto;
  padding: 40px 20px;
}

.related-section h2 {
  font-size: 24px;
  margin-bottom: 24px;
  color: #fff;
}

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

.video-card--related {
  background: #1a1a1a;
}

footer {
  background: #000;
  color: #888;
  padding: 32px 0;
  text-align: center;
  margin-top: 60px;
}

.back-to-top {
  position: fixed;
  right: 24px;
  bottom: 24px;
  width: 48px;
  height: 48px;
  background: #e50914;
  color: #fff;
  border: none;
  border-radius: 50%;
  cursor: pointer;
  display: none;
  align-items: center;
  justify-content: center;
  font-size: 20px;
  box-shadow: 0 4px 12px rgba(0,0,0,0.3);
  transition: transform 0.2s;
}

.back-to-top:hover {
  transform: scale(1.1);
}

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

@media (max-width: 768px) {
  nav ul {
    gap: 4px;
  }

  nav a {
    padding: 6px 8px;
    font-size: 12px;
  }

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

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

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

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

.site-intro {
  max-width: 1000px;
  margin: 0 auto 48px;
  padding: 32px;
  background: #1a1a1a;
  border-radius: 8px;
  color: #ccc;
  line-height: 1.8;
}

.site-intro h2 {
  color: #fff;
  font-size: 24px;
  margin-bottom: 16px;
}