/* 全局样式 */
body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  background: #f8f9fa;
  color: #212529;
  line-height: 1.8;
  font-size: 16px;
}

a { color: #007bff; text-decoration: none; transition: color 0.2s; }
a:hover { color: #0056b3; }

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

/* 首页模块 */
.intro-section {
  background: white;
  padding: 2rem;
  border-radius: 8px;
  margin-bottom: 2rem;
  box-shadow: 0 2px 8px rgba(0,0,0,0.1);
}

.intro-section h1 {
  font-size: 2rem;
  margin-bottom: 1rem;
  color: #2c3e50;
}

.intro-section p {
  font-size: 1.1rem;
  line-height: 1.8;
  color: #555;
}

section {
  background: white;
  padding: 2rem;
  border-radius: 8px;
  margin-bottom: 2rem;
  box-shadow: 0 2px 8px rgba(0,0,0,0.1);
}

section h2 {
  font-size: 1.5rem;
  margin-bottom: 1.5rem;
  color: #2c3e50;
  border-bottom: 3px solid #007bff;
  padding-bottom: 0.5rem;
}

section h3 {
  font-size: 1.3rem;
  margin: 1.5rem 0 1rem 0;
  color: #34495e;
}

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

.video-card {
  border: 1px solid #e0e0e0;
  padding: 1.5rem;
  border-radius: 6px;
  transition: transform 0.2s, box-shadow 0.2s;
}

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

.video-card h3 {
  font-size: 1.1rem;
  margin-bottom: 0.5rem;
}

.video-card .meta {
  font-size: 0.9rem;
  color: #777;
  margin-bottom: 0.5rem;
}

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

/* 视频列表 */
.video-list {
  list-style: none;
}

.video-item {
  padding: 1rem;
  border-bottom: 1px solid #eee;
  display: flex;
  align-items: center;
  gap: 1rem;
}

.video-item:last-child {
  border-bottom: none;
}

.video-item .rank {
  font-weight: bold;
  color: #007bff;
  min-width: 40px;
}

.video-item .year,
.video-item .meta {
  color: #777;
  font-size: 0.9rem;
  margin-left: auto;
}

/* 排行榜 */
.ranking-list {
  list-style: none;
  counter-reset: ranking;
}

.ranking-list li {
  display: flex;
  align-items: flex-start;
  gap: 1.5rem;
  padding: 1.5rem;
  border-bottom: 1px solid #eee;
  counter-increment: ranking;
}

.rank-num {
  font-size: 2rem;
  font-weight: bold;
  color: #007bff;
  min-width: 50px;
}

.rank-content h3 {
  margin: 0 0 0.5rem 0;
}

/* 专题网格 */
.topic-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
  gap: 1.5rem;
}

.topic-card {
  border: 1px solid #e0e0e0;
  padding: 1.5rem;
  border-radius: 6px;
}

.topic-card h4 {
  font-size: 1.1rem;
  margin-bottom: 0.5rem;
}

.topic-card .tags {
  font-size: 0.85rem;
  color: #007bff;
  margin-bottom: 0.5rem;
}

/* 时间线 */
.timeline-list {
  list-style: none;
}

.timeline-item {
  display: flex;
  gap: 1.5rem;
  padding: 1.5rem 0;
  border-left: 3px solid #007bff;
  padding-left: 1.5rem;
  margin-left: 1rem;
}

.timeline-item .date {
  font-weight: bold;
  color: #007bff;
  min-width: 60px;
}

.timeline-item h3 {
  margin: 0 0 0.5rem 0;
}

/* 详情页 */
.video-detail h1 {
  font-size: 2.5rem;
  margin-bottom: 1.5rem;
  color: #2c3e50;
}

.info-list {
  display: grid;
  grid-template-columns: auto 1fr;
  gap: 0.5rem 1rem;
  line-height: 2;
}

.info-list dt {
  font-weight: bold;
  color: #555;
}

.info-list dd {
  color: #333;
}

.highlight {
  font-size: 1.2rem;
  color: #007bff;
  font-weight: 500;
  padding: 1rem;
  background: #e7f3ff;
  border-left: 4px solid #007bff;
  border-radius: 4px;
}

.summary-section p,
.review-section p {
  font-size: 1.05rem;
  line-height: 1.9;
  text-align: justify;
}

/* 相关推荐 */
.related-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 1.5rem;
}

.related-card {
  border: 1px solid #e0e0e0;
  padding: 1.5rem;
  border-radius: 6px;
  transition: transform 0.2s, box-shadow 0.2s;
}

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

.related-card h3 {
  font-size: 1.05rem;
  margin-bottom: 0.5rem;
}

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

/* 分组展示 */
.group-section {
  margin-bottom: 2rem;
}

/* 响应式 */
@media (max-width: 768px) {
  main { padding: 0 0.5rem; margin: 1rem auto; }

  .intro-section h1 { font-size: 1.5rem; }
  .intro-section p { font-size: 1rem; }

  section { padding: 1rem; margin-bottom: 1rem; }
  section h2 { font-size: 1.3rem; }

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

  .video-detail h1 { font-size: 1.8rem; }

  .timeline-item {
    flex-direction: column;
    gap: 0.5rem;
  }

  .ranking-list li {
    flex-direction: column;
    gap: 0.5rem;
  }
}

/* UI 风格变化 */
body.ui-style-0 { --primary: #007bff; }
body.ui-style-1 { --primary: #28a745; }
body.ui-style-2 { --primary: #dc3545; }
body.ui-style-3 { --primary: #ffc107; }
body.ui-style-4 { --primary: #17a2b8; }
body.ui-style-5 { --primary: #6610f2; }
body.ui-style-6 { --primary: #e83e8c; }
body.ui-style-7 { --primary: #fd7e14; }
body.ui-style-8 { --primary: #20c997; }
body.ui-style-9 { --primary: #6c757d; }
body.ui-style-10 { --primary: #343a40; }
body.ui-style-11 { --primary: #f8f9fa; }
body.ui-style-12 { --primary: #3498db; }
body.ui-style-13 { --primary: #9b59b6; }
body.ui-style-14 { --primary: #1abc9c; }
body.ui-style-15 { --primary: #e74c3c; }