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

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, "Microsoft YaHei", sans-serif;
  background: linear-gradient(135deg, #f5f7fa 0%, #c3cfe2 100%);
  color: #333;
  line-height: 1.8;
}

nav {
  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  box-shadow: 0 2px 10px rgba(0,0,0,0.1);
  position: sticky;
  top: 0;
  z-index: 100;
}

nav ul {
  display: flex;
  flex-wrap: nowrap;
  justify-content: space-between;
  align-items: center;
  list-style: none;
  max-width: 1200px;
  margin: 0 auto;
  padding: 0;
}

nav li {
  flex: 1 1 0;
  min-width: 0;
  text-align: center;
}

nav a {
  display: block;
  padding: 1rem 0.5rem;
  color: white;
  text-decoration: none;
  font-weight: 500;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
  transition: background 0.3s;
}

nav a:hover {
  background: rgba(255, 255, 255, 0.2);
}

main {
  max-width: 1200px;
  margin: 0 auto;
  padding: 2rem 1rem;
}

.hero {
  background: white;
  padding: 3rem 2rem;
  border-radius: 12px;
  box-shadow: 0 4px 20px rgba(0,0,0,0.08);
  margin-bottom: 2rem;
  text-align: center;
}

.hero h1 {
  font-size: 2rem;
  color: #667eea;
  margin-bottom: 1rem;
}

.hero .intro {
  font-size: 1.1rem;
  color: #666;
  max-width: 800px;
  margin: 0 auto;
}

.content-section, .list-content, .detail {
  background: white;
  padding: 2rem;
  border-radius: 12px;
  box-shadow: 0 4px 20px rgba(0,0,0,0.08);
  margin-bottom: 2rem;
}

.content-section h2, .page-header h1, .detail h1 {
  font-size: 1.75rem;
  color: #667eea;
  margin-bottom: 1.5rem;
  border-left: 4px solid #667eea;
  padding-left: 1rem;
}

.video-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 1.5rem;
  margin-bottom: 1rem;
}

.video-card {
  background: #f9f9f9;
  padding: 1.5rem;
  border-radius: 8px;
  border: 1px solid #e0e0e0;
  transition: transform 0.3s, box-shadow 0.3s;
  position: relative;
}

.video-card:hover {
  transform: translateY(-4px);
  box-shadow: 0 6px 20px rgba(102, 126, 234, 0.15);
}

.video-card h3 {
  font-size: 1.2rem;
  margin-bottom: 0.5rem;
}

.video-card h3 a {
  color: #333;
  text-decoration: none;
  transition: color 0.3s;
}

.video-card h3 a:hover {
  color: #667eea;
}

.video-card .meta {
  font-size: 0.9rem;
  color: #888;
  margin-bottom: 0.5rem;
}

.video-card .desc {
  font-size: 0.95rem;
  color: #555;
  line-height: 1.6;
}

.video-card.ranked .rank {
  position: absolute;
  top: 1rem;
  right: 1rem;
  background: #667eea;
  color: white;
  padding: 0.25rem 0.75rem;
  border-radius: 20px;
  font-weight: bold;
}

.video-card .review, .video-card .tags, .video-card .date {
  font-size: 0.9rem;
  color: #666;
  margin-top: 0.5rem;
  font-style: italic;
}

.more, .links-section {
  text-align: center;
  margin-top: 1.5rem;
}

.more a, .links-section a {
  color: #667eea;
  text-decoration: none;
  font-weight: 500;
  transition: color 0.3s;
}

.more a:hover, .links-section a:hover {
  color: #764ba2;
  text-decoration: underline;
}

.page-header {
  background: white;
  padding: 2rem;
  border-radius: 12px;
  box-shadow: 0 4px 20px rgba(0,0,0,0.08);
  margin-bottom: 2rem;
  text-align: center;
}

.detail .info {
  background: #f9f9f9;
  padding: 1.5rem;
  border-radius: 8px;
  margin-bottom: 1.5rem;
}

.detail .info p {
  margin-bottom: 0.5rem;
}

.detail section {
  margin-bottom: 2rem;
}

.detail section h2 {
  font-size: 1.4rem;
  color: #667eea;
  margin-bottom: 1rem;
  border-left: 4px solid #667eea;
  padding-left: 1rem;
}

footer {
  background: #2c3e50;
  color: white;
  text-align: center;
  padding: 2rem 1rem;
  margin-top: 3rem;
}

@media (max-width: 768px) {
  nav a {
    padding: 0.75rem 0.25rem;
    font-size: 0.85rem;
  }

  .hero h1 {
    font-size: 1.5rem;
  }

  .hero .intro {
    font-size: 1rem;
  }

  .video-grid {
    grid-template-columns: 1fr;
  }

  main {
    padding: 1rem 0.5rem;
  }
}