:root {
  --primary-color: #3498db;
  --secondary-color: #2c3e50;
  --bg-color: #f8f9fa;
  --card-bg: #ffffff;
  --border-color: #e0e0e0;
  --text-color: #2c3e50;
  --text-light: #7f8c8d;
}

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

.page-header {
  text-align: center;
  margin-bottom: 2rem;
  padding: 2rem 1rem;
  background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
  color: white;
  border-radius: 8px;
}

.site-title {
  font-size: 2rem;
  margin: 0;
  line-height: 1.4;
}

.site-intro {
  background: var(--card-bg);
  padding: 1.5rem;
  border-radius: 8px;
  margin-bottom: 2rem;
  border-left: 4px solid var(--primary-color);
  line-height: 1.8;
}

section {
  margin-bottom: 3rem;
}

section h2 {
  font-size: 1.5rem;
  margin-bottom: 1rem;
  padding-bottom: 0.5rem;
  border-bottom: 2px solid var(--primary-color);
}

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

.video-card {
  background: var(--card-bg);
  padding: 1.5rem;
  border-radius: 8px;
  box-shadow: 0 2px 8px rgba(0,0,0,0.1);
  transition: transform 0.3s, box-shadow 0.3s;
}

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

.video-card h3 {
  margin: 0 0 0.5rem 0;
  font-size: 1.2rem;
}

.video-card .meta {
  color: var(--text-light);
  font-size: 0.9rem;
  margin: 0.5rem 0;
}

.video-card .one-line {
  color: var(--text-color);
  margin: 0.5rem 0 0 0;
  line-height: 1.6;
}

.video-card .tags {
  font-size: 0.85rem;
  color: var(--text-light);
}

.video-card .summary {
  font-size: 0.95rem;
  color: var(--text-color);
  line-height: 1.6;
}

.links-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 1rem;
}

.link-card {
  background: var(--primary-color);
  color: white;
  padding: 1.5rem;
  text-align: center;
  border-radius: 8px;
  font-weight: bold;
  transition: background 0.3s;
}

.link-card:hover {
  background: var(--secondary-color);
  text-decoration: none;
}

.video-list {
  list-style: none;
  padding: 0;
}

.video-list li {
  background: var(--card-bg);
  padding: 1rem 1.5rem;
  margin-bottom: 0.5rem;
  border-radius: 4px;
  display: flex;
  align-items: center;
  gap: 1rem;
}

.video-list li a {
  flex: 1;
  font-weight: 500;
}

.video-list .year,
.video-list .genre {
  color: var(--text-light);
  font-size: 0.9rem;
}

.ranked-list {
  list-style: none;
  padding: 0;
  counter-reset: rank;
}

.ranked-item {
  background: var(--card-bg);
  padding: 1.5rem;
  margin-bottom: 1rem;
  border-radius: 8px;
  display: flex;
  gap: 1.5rem;
  align-items: flex-start;
}

.rank-num {
  display: inline-block;
  width: 40px;
  height: 40px;
  background: var(--primary-color);
  color: white;
  border-radius: 50%;
  text-align: center;
  line-height: 40px;
  font-weight: bold;
  font-size: 1.2rem;
  flex-shrink: 0;
}

.rank-content {
  flex: 1;
}

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

.topic-group {
  margin-bottom: 3rem;
}

.topic-title {
  background: var(--secondary-color);
  color: white;
  padding: 0.75rem 1.5rem;
  border-radius: 4px;
  margin-bottom: 1rem;
}

.latest-list {
  list-style: none;
  padding: 0;
}

.latest-item {
  background: var(--card-bg);
  padding: 1.5rem;
  margin-bottom: 1rem;
  border-radius: 8px;
  display: flex;
  gap: 1rem;
}

.date-tag {
  background: var(--primary-color);
  color: white;
  padding: 0.5rem 1rem;
  border-radius: 4px;
  font-weight: bold;
  align-self: flex-start;
}

.item-content {
  flex: 1;
}

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

.detail-page .basic-info dl {
  display: grid;
  grid-template-columns: 100px 1fr;
  gap: 0.75rem 1rem;
  background: var(--card-bg);
  padding: 1.5rem;
  border-radius: 8px;
}

.detail-page .basic-info dt {
  font-weight: bold;
  color: var(--text-light);
}

.detail-page .basic-info dd {
  margin: 0;
}

.detail-page .highlight,
.detail-page .summary,
.detail-page .review {
  background: var(--card-bg);
  padding: 1.5rem;
  border-radius: 8px;
  line-height: 1.8;
}

.detail-page .highlight p {
  font-size: 1.1rem;
  color: var(--primary-color);
  font-weight: 500;
  margin: 0;
}

@media (max-width: 767px) {
  .container {
    padding: 1rem 0.5rem;
  }
  .site-title {
    font-size: 1.5rem;
  }
  .video-grid {
    grid-template-columns: 1fr;
  }
  .detail-page .basic-info dl {
    grid-template-columns: 80px 1fr;
  }
}