/* UI Style 7 - Layout D */
* {
  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: #2c3e50;
  background: linear-gradient(135deg, #f5f7fa 0%, #e8edf2 100%);
  min-height: 100vh;
}

.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 20px;
}

/* 导航栏 */
header {
  background: linear-gradient(to right, #34495e, #2c3e50);
  box-shadow: 0 2px 10px rgba(0,0,0,0.1);
  position: sticky;
  top: 0;
  z-index: 100;
}

nav {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 0;
  flex-wrap: nowrap;
}

.logo {
  font-size: 1.5rem;
  font-weight: bold;
  color: #ecf0f1;
  text-decoration: none;
  padding: 1rem 0;
  white-space: nowrap;
  flex-shrink: 0;
  margin-right: 1rem;
}

.nav-links {
  display: flex;
  list-style: none;
  gap: 0;
  flex: 1;
  justify-content: flex-end;
  flex-wrap: nowrap;
}

.nav-links li {
  flex: 0 1 auto;
  min-width: 0;
}

.nav-links a {
  color: #ecf0f1;
  text-decoration: none;
  padding: 1rem 0.8rem;
  display: block;
  transition: all 0.3s;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.nav-links a:hover {
  background: rgba(255,255,255,0.1);
  color: #3498db;
}

/* 主内容 */
main {
  padding: 2rem 0;
  min-height: calc(100vh - 200px);
}

.page-header {
  text-align: center;
  margin-bottom: 3rem;
  padding: 2rem 0;
}

.page-header h1 {
  font-size: 2.2rem;
  color: #2c3e50;
  margin-bottom: 1rem;
  font-weight: 700;
}

.page-intro {
  max-width: 800px;
  margin: 2rem auto;
  padding: 2rem;
  background: white;
  border-radius: 10px;
  box-shadow: 0 2px 15px rgba(0,0,0,0.08);
  line-height: 1.8;
  color: #555;
}

/* 区块模块 */
.section {
  margin-bottom: 3rem;
  background: white;
  padding: 2rem;
  border-radius: 10px;
  box-shadow: 0 2px 15px rgba(0,0,0,0.08);
}

.section-title {
  font-size: 1.8rem;
  color: #2c3e50;
  margin-bottom: 1.5rem;
  padding-bottom: 0.5rem;
  border-bottom: 3px solid #3498db;
}

/* 视频卡片 */
.video-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 1.5rem;
}

.video-card {
  background: #fff;
  border-radius: 8px;
  padding: 1.5rem;
  box-shadow: 0 2px 8px rgba(0,0,0,0.1);
  transition: all 0.3s;
  border-left: 4px solid #3498db;
}

.video-card:hover {
  transform: translateY(-5px);
  box-shadow: 0 4px 20px rgba(52,152,219,0.3);
}

.video-card h3 {
  font-size: 1.2rem;
  color: #2c3e50;
  margin-bottom: 0.8rem;
}

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

.video-card h3 a:hover {
  color: #3498db;
}

.video-meta {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
  margin-bottom: 0.8rem;
  font-size: 0.9rem;
  color: #7f8c8d;
}

.video-meta span {
  background: #ecf0f1;
  padding: 0.2rem 0.6rem;
  border-radius: 4px;
}

.video-summary {
  color: #555;
  font-size: 0.95rem;
  line-height: 1.6;
  margin-bottom: 1rem;
  display: -webkit-box;
  -webkit-line-clamp: 3;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

.video-link {
  display: inline-block;
  padding: 0.5rem 1.2rem;
  background: #3498db;
  color: white;
  text-decoration: none;
  border-radius: 5px;
  transition: all 0.3s;
  font-size: 0.9rem;
}

.video-link:hover {
  background: #2980b9;
  transform: scale(1.05);
}

/* 详情页 */
.detail-container {
  max-width: 900px;
  margin: 0 auto;
  background: white;
  padding: 3rem;
  border-radius: 10px;
  box-shadow: 0 2px 20px rgba(0,0,0,0.1);
}

.detail-title {
  font-size: 2.5rem;
  color: #2c3e50;
  margin-bottom: 2rem;
  padding-bottom: 1rem;
  border-bottom: 3px solid #3498db;
}

.detail-meta {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 1rem;
  margin-bottom: 2rem;
  padding: 1.5rem;
  background: #f8f9fa;
  border-radius: 8px;
}

.meta-item {
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.meta-label {
  font-weight: 600;
  color: #34495e;
}

.meta-value {
  color: #555;
}

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

.detail-section h2 {
  font-size: 1.5rem;
  color: #2c3e50;
  margin-bottom: 1rem;
  padding-left: 1rem;
  border-left: 4px solid #3498db;
}

.detail-section p, .detail-section ul {
  color: #555;
  line-height: 1.8;
  margin-bottom: 1rem;
}

.tags {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
  margin-top: 0.5rem;
}

.tag {
  background: #3498db;
  color: white;
  padding: 0.3rem 0.8rem;
  border-radius: 15px;
  font-size: 0.85rem;
}

.review-box {
  background: #fff3cd;
  border-left: 4px solid #ffc107;
  padding: 1.5rem;
  border-radius: 5px;
  margin: 1.5rem 0;
  font-style: italic;
  color: #856404;
}

/* 相关推荐 */
.related-section {
  margin-top: 3rem;
  padding-top: 2rem;
  border-top: 2px solid #ecf0f1;
}

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

.related-item {
  background: #f8f9fa;
  padding: 1.2rem;
  border-radius: 8px;
  transition: all 0.3s;
}

.related-item:hover {
  background: #e9ecef;
  transform: translateX(5px);
}

.related-item h4 {
  font-size: 1.1rem;
  margin-bottom: 0.5rem;
}

.related-item h4 a {
  color: #2c3e50;
  text-decoration: none;
}

.related-item h4 a:hover {
  color: #3498db;
}

.related-item p {
  font-size: 0.9rem;
  color: #666;
  margin: 0;
}

/* 列表页 */
.video-list {
  display: flex;
  flex-direction: column;
  gap: 1.5rem;
}

.list-item {
  background: white;
  padding: 1.5rem;
  border-radius: 8px;
  box-shadow: 0 2px 8px rgba(0,0,0,0.08);
  transition: all 0.3s;
  border-left: 4px solid #3498db;
}

.list-item:hover {
  box-shadow: 0 4px 15px rgba(52,152,219,0.3);
  transform: translateX(5px);
}

.list-item-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 1rem;
}

.list-item-header h3 {
  font-size: 1.3rem;
  color: #2c3e50;
}

.list-item-header h3 a {
  color: inherit;
  text-decoration: none;
}

.list-item-header h3 a:hover {
  color: #3498db;
}

.list-rank {
  font-size: 1.5rem;
  font-weight: bold;
  color: #3498db;
  min-width: 40px;
  text-align: center;
}

.list-content p {
  color: #555;
  line-height: 1.7;
  margin-bottom: 0.8rem;
}

/* Footer */
footer {
  background: #2c3e50;
  color: #ecf0f1;
  text-align: center;
  padding: 2rem 0;
  margin-top: 3rem;
}

/* 响应式 */
@media (max-width: 768px) {
  .logo {
    font-size: 1.2rem;
    padding: 0.8rem 0;
    margin-right: 0.5rem;
  }
  
  .nav-links {
    gap: 0;
  }
  
  .nav-links a {
    padding: 0.8rem 0.5rem;
    font-size: 0.85rem;
  }
  
  .page-header h1 {
    font-size: 1.6rem;
  }
  
  .detail-container {
    padding: 1.5rem;
  }
  
  .detail-title {
    font-size: 1.8rem;
  }
  
  .video-grid {
    grid-template-columns: 1fr;
  }
  
  .detail-meta {
    grid-template-columns: 1fr;
  }
}

@media (max-width: 480px) {
  .logo {
    font-size: 1rem;
  }
  
  .nav-links a {
    padding: 0.8rem 0.3rem;
    font-size: 0.75rem;
  }
  
  .container {
    padding: 0 15px;
  }
}