/* 基础样式 */
* { box-sizing: border-box; }
body {
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  line-height: 1.6;
  color: #333;
  background: #f8f9fa;
}
a { text-decoration: none; color: #007bff; transition: color 0.2s; }
a:hover { color: #0056b3; }
ul, ol { list-style: none; padding: 0; margin: 0; }
img { max-width: 100%; height: auto; }

/* 导航栏 */
header {
  background: #fff;
  box-shadow: 0 2px 4px rgba(0,0,0,0.1);
  position: sticky;
  top: 0;
  z-index: 1000;
}
header nav {
  display: flex;
  flex-wrap: nowrap;
  justify-content: space-between;
  align-items: center;
  max-width: 1200px;
  margin: 0 auto;
  padding: 0;
}
header nav a {
  flex: 1 1 0;
  min-width: 0;
  text-align: center;
  padding: 1rem 0.5rem;
  color: #333;
  font-weight: 500;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
  border-bottom: 3px solid transparent;
}
header nav a:hover {
  color: #007bff;
  border-bottom-color: #007bff;
}

/* 移动端导航 - 硬性要求：单行不换行不滚动 */
@media (max-width: 768px) {
  header nav {
    flex-wrap: nowrap;
    overflow: visible;
  }
  header nav a {
    flex: 1 1 0;
    min-width: 0;
    padding: 0.75rem 0.25rem;
    font-size: 0.85rem;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
  }
}

/* 主体容器 */
main {
  max-width: 1200px;
  margin: 2rem auto;
  padding: 0 1rem;
  min-height: 60vh;
}

/* 首页样式 */
.hero {
  text-align: center;
  padding: 3rem 1rem;
  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  color: #fff;
  border-radius: 8px;
  margin-bottom: 2rem;
}
.hero h1 {
  margin: 0 0 1rem 0;
  font-size: 2rem;
}
.hero .subtitle {
  font-size: 1.1rem;
  opacity: 0.95;
}

.intro {
  background: #fff;
  padding: 2rem;
  border-radius: 8px;
  margin-bottom: 2rem;
  box-shadow: 0 2px 4px rgba(0,0,0,0.05);
}
.intro h2 {
  color: #333;
  margin-top: 0;
}
.intro p {
  color: #666;
  line-height: 1.8;
}

.section {
  margin-bottom: 3rem;
}
.section-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 1rem;
}
.section-header h2 {
  margin: 0;
  color: #333;
}
.more-link {
  color: #007bff;
  font-size: 0.95rem;
}

.quick-links {
  background: #fff;
  padding: 2rem;
  border-radius: 8px;
  box-shadow: 0 2px 4px rgba(0,0,0,0.05);
}
.quick-links h2 {
  margin-top: 0;
}
.quick-links ul {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 1rem;
}
.quick-links li a {
  display: block;
  padding: 1rem;
  background: #f8f9fa;
  border-radius: 4px;
  text-align: center;
  transition: all 0.2s;
}
.quick-links li a:hover {
  background: #007bff;
  color: #fff;
  transform: translateY(-2px);
}

/* 视频网格 */
.video-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 1.5rem;
}
.video-grid li {
  background: #fff;
  border-radius: 8px;
  overflow: hidden;
  box-shadow: 0 2px 8px rgba(0,0,0,0.08);
  transition: all 0.3s;
}
.video-grid li:hover {
  transform: translateY(-4px);
  box-shadow: 0 4px 16px rgba(0,0,0,0.15);
}
.video-grid li a {
  display: block;
  padding: 1.5rem;
  color: #333;
}
.video-grid li h3 {
  margin: 0 0 0.5rem 0;
  font-size: 1.1rem;
  color: #333;
}
.video-grid li p {
  margin: 0;
  color: #666;
  font-size: 0.9rem;
  line-height: 1.5;
}

/* 视频列表 */
.video-list {
  background: #fff;
  border-radius: 8px;
  overflow: hidden;
  box-shadow: 0 2px 4px rgba(0,0,0,0.05);
}
.video-list li {
  border-bottom: 1px solid #eee;
}
.video-list li:last-child {
  border-bottom: none;
}
.video-list li a {
  display: block;
  padding: 1.25rem 1.5rem;
  color: #333;
  transition: background 0.2s;
}
.video-list li a:hover {
  background: #f8f9fa;
}
.video-list li h3 {
  margin: 0 0 0.5rem 0;
  font-size: 1.05rem;
  color: #333;
}
.video-list li p {
  margin: 0;
  color: #666;
  font-size: 0.9rem;
}

/* 列表页完整版 */
.list-page h1 {
  margin-top: 0;
  color: #333;
}
.page-desc {
  color: #666;
  margin-bottom: 2rem;
  font-size: 1.05rem;
}

.video-list-full {
  display: grid;
  gap: 1rem;
}
.video-item {
  background: #fff;
  border-radius: 8px;
  overflow: hidden;
  box-shadow: 0 2px 4px rgba(0,0,0,0.05);
  transition: all 0.2s;
}
.video-item:hover {
  box-shadow: 0 4px 12px rgba(0,0,0,0.1);
}
.video-item a {
  display: block;
  padding: 1.5rem;
  color: #333;
}
.video-item h3 {
  margin: 0 0 0.5rem 0;
  color: #333;
}
.video-item .meta {
  color: #999;
  font-size: 0.85rem;
  margin-bottom: 0.5rem;
}
.video-item p {
  margin: 0;
  color: #666;
  font-size: 0.95rem;
}

/* 排行榜样式 */
.video-list-ranked .video-item {
  position: relative;
  padding-left: 4rem;
}
.video-item.ranked .rank {
  position: absolute;
  left: 1.5rem;
  top: 50%;
  transform: translateY(-50%);
  font-size: 1.5rem;
  font-weight: bold;
  color: #007bff;
}

/* 专题组 */
.topic-group {
  margin-bottom: 3rem;
}
.topic-group h2 {
  color: #333;
  margin-bottom: 1rem;
}

/* 详情页 */
.detail-page article {
  background: #fff;
  padding: 2.5rem;
  border-radius: 8px;
  box-shadow: 0 2px 4px rgba(0,0,0,0.05);
}
.detail-page h1 {
  margin-top: 0;
  color: #333;
  font-size: 2rem;
  border-bottom: 3px solid #007bff;
  padding-bottom: 1rem;
}
.detail-page section {
  margin-bottom: 2.5rem;
}
.detail-page h2 {
  color: #333;
  font-size: 1.3rem;
  margin-bottom: 1rem;
  border-left: 4px solid #007bff;
  padding-left: 1rem;
}
.basic-info ul {
  list-style: none;
  padding: 0;
}
.basic-info li {
  padding: 0.5rem 0;
  border-bottom: 1px solid #eee;
}
.basic-info li:last-child {
  border-bottom: none;
}
.basic-info strong {
  color: #555;
  min-width: 80px;
  display: inline-block;
}
.one-line p {
  font-size: 1.1rem;
  color: #007bff;
  font-weight: 500;
  line-height: 1.6;
}
.summary p, .review p {
  color: #555;
  line-height: 1.8;
  font-size: 1rem;
}

/* 页脚 */
footer {
  background: #333;
  color: #fff;
  text-align: center;
  padding: 2rem 1rem;
  margin-top: 4rem;
}
footer p {
  margin: 0;
}

/* 响应式 */
@media (max-width: 768px) {
  .hero h1 { font-size: 1.5rem; }
  .hero .subtitle { font-size: 1rem; }
  .video-grid { grid-template-columns: 1fr; }
  .detail-page article { padding: 1.5rem; }
  .detail-page h1 { font-size: 1.5rem; }
  main { padding: 0 0.75rem; }
}