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

.main-content {
  min-height: calc(100vh - 200px);
  padding: 40px 0;
}

.page-title {
  font-size: 32px;
  margin-bottom: 30px;
  color: #1a1a1a;
  text-align: center;
}

.site-intro, .page-intro, .topic-intro {
  background: #fff;
  padding: 30px;
  border-radius: 8px;
  margin-bottom: 40px;
  line-height: 1.8;
  box-shadow: 0 2px 8px rgba(0,0,0,0.05);
}

.site-intro p, .page-intro p, .topic-intro p {
  margin-bottom: 15px;
}

.site-intro a, .page-intro a, .topic-intro a {
  color: #1a73e8;
  text-decoration: none;
  border-bottom: 1px solid #1a73e8;
}

.site-intro a:hover, .page-intro a:hover, .topic-intro a:hover {
  color: #0d47a1;
  border-bottom-color: #0d47a1;
}

section {
  margin-bottom: 50px;
}

section h2 {
  font-size: 24px;
  margin-bottom: 20px;
  color: #333;
  border-left: 4px solid #1a73e8;
  padding-left: 15px;
}

.video-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 20px;
  margin-bottom: 30px;
}

.video-card {
  background: #fff;
  border-radius: 8px;
  padding: 20px;
  box-shadow: 0 2px 8px rgba(0,0,0,0.08);
  transition: transform 0.3s, box-shadow 0.3s;
}

.video-card:hover {
  transform: translateY(-5px);
  box-shadow: 0 4px 16px rgba(0,0,0,0.15);
}

.video-card h3 {
  font-size: 18px;
  margin-bottom: 10px;
}

.video-card h3 a {
  color: #1a1a1a;
  text-decoration: none;
  transition: color 0.3s;
}

.video-card h3 a:hover {
  color: #1a73e8;
}

.video-meta {
  display: flex;
  gap: 10px;
  flex-wrap: wrap;
  margin: 10px 0;
  font-size: 14px;
}

.video-meta span {
  background: #f0f0f0;
  padding: 3px 10px;
  border-radius: 4px;
  color: #666;
}

.video-desc {
  color: #555;
  line-height: 1.6;
  margin: 15px 0;
  font-size: 14px;
}

.read-more {
  display: inline-block;
  color: #1a73e8;
  text-decoration: none;
  font-size: 14px;
  margin-top: 10px;
  transition: color 0.3s;
}

.read-more:hover {
  color: #0d47a1;
}

.video-list {
  background: #fff;
  border-radius: 8px;
  padding: 20px;
  box-shadow: 0 2px 8px rgba(0,0,0,0.05);
}

.video-item {
  padding: 20px 0;
  border-bottom: 1px solid #eee;
}

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

.video-item h3 {
  font-size: 18px;
  margin-bottom: 10px;
}

.video-item h3 a {
  color: #1a1a1a;
  text-decoration: none;
}

.video-item h3 a:hover {
  color: #1a73e8;
}

.video-item p {
  color: #666;
  line-height: 1.6;
  margin-top: 10px;
}

.more-link {
  text-align: center;
  margin-top: 30px;
}

.more-link a {
  display: inline-block;
  padding: 12px 30px;
  background: #1a73e8;
  color: #fff;
  text-decoration: none;
  border-radius: 6px;
  transition: background 0.3s;
}

.more-link a:hover {
  background: #0d47a1;
}

.nav-cards {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 20px;
}

.nav-card {
  background: #fff;
  padding: 30px;
  border-radius: 8px;
  box-shadow: 0 2px 8px rgba(0,0,0,0.08);
  transition: transform 0.3s;
}

.nav-card:hover {
  transform: translateY(-3px);
}

.nav-card h3 {
  font-size: 20px;
  margin-bottom: 15px;
}

.nav-card h3 a {
  color: #1a73e8;
  text-decoration: none;
}

.nav-card h3 a:hover {
  color: #0d47a1;
}

.nav-card p {
  color: #666;
  line-height: 1.6;
}

.year-group {
  margin-bottom: 50px;
}

.year-title {
  font-size: 28px;
  color: #1a73e8;
  margin-bottom: 25px;
  padding-bottom: 10px;
  border-bottom: 2px solid #e0e0e0;
}

.ranking-list {
  background: #fff;
  border-radius: 8px;
  padding: 20px;
  box-shadow: 0 2px 8px rgba(0,0,0,0.05);
}

.ranking-item {
  display: flex;
  gap: 20px;
  padding: 25px 0;
  border-bottom: 1px solid #eee;
}

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

.rank-number {
  flex-shrink: 0;
  width: 50px;
  height: 50px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: #1a73e8;
  color: #fff;
  font-size: 24px;
  font-weight: bold;
  border-radius: 8px;
}

.rank-content {
  flex: 1;
}

.rank-content h3 {
  font-size: 20px;
  margin-bottom: 12px;
}

.rank-content h3 a {
  color: #1a1a1a;
  text-decoration: none;
}

.rank-content h3 a:hover {
  color: #1a73e8;
}

.tags {
  display: flex;
  gap: 8px;
  flex-wrap: wrap;
  margin: 12px 0;
}

.tag {
  background: #e3f2fd;
  color: #1a73e8;
  padding: 4px 12px;
  border-radius: 4px;
  font-size: 13px;
}

.recommend-reason {
  color: #555;
  line-height: 1.8;
  margin: 15px 0;
}

.topic-list {
  background: #fff;
  border-radius: 8px;
  padding: 20px;
  box-shadow: 0 2px 8px rgba(0,0,0,0.05);
}

.topic-item {
  padding: 30px 0;
  border-bottom: 1px solid #eee;
}

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

.topic-item h3 {
  font-size: 22px;
  margin-bottom: 15px;
}

.topic-item h3 a {
  color: #1a1a1a;
  text-decoration: none;
}

.topic-item h3 a:hover {
  color: #1a73e8;
}

.topic-desc {
  color: #555;
  line-height: 1.8;
  margin: 15px 0;
  font-size: 15px;
}

.latest-list {
  background: #fff;
  border-radius: 8px;
  padding: 20px;
  box-shadow: 0 2px 8px rgba(0,0,0,0.05);
}

.latest-item {
  display: flex;
  gap: 20px;
  padding: 20px 0;
  border-bottom: 1px solid #eee;
}

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

.latest-date {
  flex-shrink: 0;
  background: #f5f5f5;
  padding: 10px 15px;
  border-radius: 6px;
  font-weight: bold;
  color: #666;
  font-size: 14px;
  height: fit-content;
}

.latest-content {
  flex: 1;
}

.latest-content h3 {
  font-size: 18px;
  margin-bottom: 10px;
}

.latest-content h3 a {
  color: #1a1a1a;
  text-decoration: none;
}

.latest-content h3 a:hover {
  color: #1a73e8;
}

.latest-desc {
  color: #666;
  line-height: 1.6;
  margin: 10px 0;
}

.detail-page {
  background: #fff;
  border-radius: 8px;
  padding: 40px;
  box-shadow: 0 2px 8px rgba(0,0,0,0.05);
}

.detail-title {
  font-size: 32px;
  margin-bottom: 30px;
  color: #1a1a1a;
  text-align: left;
}

.detail-meta, .detail-oneline, .detail-summary, .detail-review, .detail-related {
  margin-bottom: 40px;
}

.detail-meta h2, .detail-oneline h2, .detail-summary h2, .detail-review h2, .detail-related h2 {
  font-size: 22px;
  margin-bottom: 20px;
  color: #333;
  border-left: 4px solid #1a73e8;
  padding-left: 15px;
}

.detail-meta dl {
  display: grid;
  grid-template-columns: 120px 1fr;
  gap: 15px;
  line-height: 1.8;
}

.detail-meta dt {
  font-weight: bold;
  color: #666;
}

.detail-meta dd {
  color: #333;
}

.highlight-text {
  font-size: 18px;
  line-height: 1.8;
  color: #1a73e8;
  font-weight: 500;
  padding: 20px;
  background: #f0f7ff;
  border-radius: 6px;
}

.summary-text, .review-text {
  line-height: 1.9;
  color: #444;
  font-size: 16px;
}

.summary-text p, .review-text p {
  margin-bottom: 15px;
}

.site-footer {
  background: #2c3e50;
  color: #ecf0f1;
  padding: 40px 0 20px;
  margin-top: 60px;
}

.footer-nav {
  display: flex;
  justify-content: center;
  gap: 30px;
  margin-bottom: 20px;
  flex-wrap: wrap;
}

.footer-nav a {
  color: #ecf0f1;
  text-decoration: none;
  transition: color 0.3s;
}

.footer-nav a:hover {
  color: #3498db;
}

.copyright {
  text-align: center;
  color: #95a5a6;
  font-size: 14px;
}

@media (max-width: 768px) {
  .container {
    padding: 15px;
  }

  .page-title {
    font-size: 24px;
  }

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

  .nav-cards {
    grid-template-columns: 1fr;
  }

  .ranking-item {
    flex-direction: column;
  }

  .rank-number {
    width: 40px;
    height: 40px;
    font-size: 20px;
  }

  .latest-item {
    flex-direction: column;
    gap: 10px;
  }

  .detail-page {
    padding: 20px;
  }

  .detail-title {
    font-size: 24px;
  }

  .detail-meta dl {
    grid-template-columns: 80px 1fr;
    gap: 10px;
  }
}