* {
  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;
  background: #f5f5f5;
}

.ui-style-9 {
  --primary-color: #ff6b6b;
  --bg-color: #ffffff;
  --text-color: #333333;
}

.main-nav {
  background: var(--bg-color);
  padding: 1rem 2rem;
  display: flex;
  gap: 2rem;
  align-items: center;
  box-shadow: 0 2px 4px rgba(0,0,0,0.1);
  flex-wrap: nowrap;
  overflow-x: auto;
}

.main-nav a {
  color: var(--text-color);
  text-decoration: none;
  white-space: nowrap;
  transition: color 0.3s;
}

.main-nav a:hover {
  color: var(--primary-color);
}

.logo {
  font-weight: bold;
  font-size: 1.5rem;
}

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

.hero {
  text-align: center;
  padding: 3rem 1rem;
  background: var(--bg-color);
  border-radius: 8px;
  margin-bottom: 2rem;
}

.hero h1 {
  font-size: 1.8rem;
  margin-bottom: 1rem;
  color: var(--text-color);
}

.site-intro {
  font-size: 1rem;
  color: #666;
  max-width: 800px;
  margin: 0 auto;
}

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

.video-section h2 {
  font-size: 1.5rem;
  margin-bottom: 1.5rem;
  color: var(--text-color);
}

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

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

.video-card:hover {
  transform: translateY(-4px);
  box-shadow: 0 4px 12px rgba(0,0,0,0.15);
}

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

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

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

.video-info {
  padding: 1rem;
}

.video-title {
  font-size: 1rem;
  font-weight: 600;
  margin-bottom: 0.5rem;
  color: var(--text-color);
}

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

.page-header {
  text-align: center;
  padding: 2rem 1rem;
  margin-bottom: 2rem;
}

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

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

.video-player {
  width: 100%;
  max-width: 1200px;
  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;
  border-radius: 50%;
  background: rgba(255,255,255,0.9);
  border: none;
  cursor: pointer;
  transition: transform 0.3s;
}

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

.player-play-icon {
  font-size: 2rem;
  color: #333;
}

.detail-title {
  text-align: center;
  padding: 2rem 1rem;
}

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

.detail-info, .detail-module, .related-section {
  background: var(--bg-color);
  padding: 2rem;
  border-radius: 8px;
  margin-bottom: 2rem;
}

.detail-info h2, .detail-module h2, .related-section h2 {
  font-size: 1.5rem;
  margin-bottom: 1rem;
  color: var(--text-color);
}

.detail-info dl {
  display: grid;
  grid-template-columns: auto 1fr;
  gap: 0.5rem 1rem;
}

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

.detail-module p {
  color: #555;
  line-height: 1.8;
}

footer {
  text-align: center;
  padding: 2rem;
  color: #666;
  background: var(--bg-color);
  margin-top: 3rem;
}

@media (max-width: 768px) {
  .main-nav {
    padding: 1rem;
    gap: 1rem;
  }

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

  .hero h1 {
    font-size: 1.3rem;
  }

  .video-cover {
    padding-top: 45%;
  }
}