/* UI Style: ui-style-15, Layout: A */

:root {
  --primary-color: #2563eb;
  --secondary-color: #64748b;
  --accent-color: #f59e0b;
  --bg-color: #f8fafc;
  --card-bg: #ffffff;
  --text-color: #1e293b;
  --text-secondary: #64748b;
  --border-color: #e2e8f0;
  --hover-bg: #f1f5f9;
}

body {
  background: var(--bg-color);
  color: var(--text-color);
  font-size: 16px;
}

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

/* Hero Section */
.hero {
  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  color: white;
  padding: 3rem 2rem;
  border-radius: 12px;
  margin-bottom: 2rem;
  text-align: center;
}

.hero h1 {
  font-size: 2rem;
  margin-bottom: 1rem;
  font-weight: 700;
}

.hero .intro {
  font-size: 1.1rem;
  line-height: 1.8;
  margin-bottom: 1rem;
  opacity: 0.95;
}

.hero .tags {
  font-size: 0.9rem;
  opacity: 0.85;
}

/* Sections */
section {
  margin-bottom: 3rem;
}

section h2 {
  font-size: 1.75rem;
  margin-bottom: 1.5rem;
  padding-bottom: 0.5rem;
  border-bottom: 3px solid var(--primary-color);
  color: var(--text-color);
}

.intro-section p {
  line-height: 1.8;
  color: var(--text-secondary);
  font-size: 1.05rem;
}

/* Video Grid */
.video-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
  gap: 1.5rem;
}

.video-card {
  background: var(--card-bg);
  padding: 1.5rem;
  border-radius: 8px;
  box-shadow: 0 2px 8px rgba(0,0,0,0.08);
  transition: transform 0.3s, box-shadow 0.3s;
}

.video-card:hover {
  transform: translateY(-4px);
  box-shadow: 0 4px 16px rgba(0,0,0,0.12);
}

.video-card h3 {
  font-size: 1.25rem;
  margin-bottom: 0.75rem;
}

.video-card h3 a {
  color: var(--text-color);
}

.video-card h3 a:hover {
  color: var(--primary-color);
}

.video-card .meta {
  color: var(--text-secondary);
  font-size: 0.9rem;
  margin-bottom: 0.75rem;
}

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

/* List Pages */
.list-page h1 {
  font-size: 2.5rem;
  margin-bottom: 1rem;
  color: var(--text-color);
}

.page-desc {
  font-size: 1.1rem;
  color: var(--text-secondary);
  margin-bottom: 2rem;
  line-height: 1.8;
}

.video-list {
  display: flex;
  flex-direction: column;
  gap: 1.5rem;
}

.video-item {
  background: var(--card-bg);
  padding: 1.5rem;
  border-radius: 8px;
  box-shadow: 0 2px 8px rgba(0,0,0,0.08);
  transition: transform 0.3s, box-shadow 0.3s;
}

.video-item:hover {
  transform: translateX(4px);
  box-shadow: 0 4px 16px rgba(0,0,0,0.12);
}

.top-item .rank {
  display: inline-block;
  width: 32px;
  height: 32px;
  background: var(--primary-color);
  color: white;
  text-align: center;
  line-height: 32px;
  border-radius: 50%;
  font-weight: bold;
  margin-right: 1rem;
}

.latest-item .year {
  display: inline-block;
  background: var(--accent-color);
  color: white;
  padding: 0.25rem 0.75rem;
  border-radius: 4px;
  font-size: 0.9rem;
  margin-right: 1rem;
}

.video-item h3 {
  font-size: 1.5rem;
  margin-bottom: 0.75rem;
  display: inline;
}

.video-item h3 a {
  color: var(--text-color);
}

.video-item h3 a:hover {
  color: var(--primary-color);
}

/* Detail Page */
.detail-page article {
  background: var(--card-bg);
  padding: 2.5rem;
  border-radius: 12px;
  box-shadow: 0 2px 12px rgba(0,0,0,0.08);
}

.detail-page h1 {
  font-size: 2.5rem;
  margin-bottom: 2rem;
  color: var(--text-color);
  padding-bottom: 1rem;
  border-bottom: 3px solid var(--primary-color);
}

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

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

.info ul {
  list-style: none;
}

.info li {
  padding: 0.5rem 0;
  border-bottom: 1px solid var(--border-color);
}

.info li:last-child {
  border-bottom: none;
}

.info strong {
  color: var(--text-color);
  margin-right: 0.5rem;
}

.highlight p {
  font-size: 1.2rem;
  line-height: 1.8;
  color: var(--primary-color);
  font-weight: 500;
  font-style: italic;
  padding: 1rem;
  background: var(--hover-bg);
  border-left: 4px solid var(--primary-color);
  border-radius: 4px;
}

.summary p, .review p {
  line-height: 1.8;
  color: var(--text-secondary);
  font-size: 1.05rem;
}

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

.related-item {
  background: var(--hover-bg);
  padding: 1rem;
  border-radius: 6px;
  transition: background 0.3s;
}

.related-item:hover {
  background: var(--border-color);
}

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

.related-item h4 a {
  color: var(--text-color);
}

.related-item h4 a:hover {
  color: var(--primary-color);
}

.related-item p {
  font-size: 0.9rem;
  color: var(--text-secondary);
  line-height: 1.6;
}

/* Links & More */
.more-link {
  text-align: center;
  margin-top: 1.5rem;
}

.more-link a {
  font-size: 1.1rem;
  color: var(--primary-color);
  font-weight: 500;
}

.link-list {
  list-style: none;
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
  gap: 1rem;
}

.link-list li a {
  display: block;
  background: var(--card-bg);
  padding: 1rem 1.5rem;
  border-radius: 6px;
  box-shadow: 0 2px 6px rgba(0,0,0,0.06);
  transition: all 0.3s;
  color: var(--text-color);
  font-weight: 500;
}

.link-list li a:hover {
  background: var(--primary-color);
  color: white;
  transform: translateY(-2px);
  box-shadow: 0 4px 12px rgba(0,0,0,0.1);
}

/* Footer */
footer {
  text-align: center;
  padding: 2rem 1rem;
  color: var(--text-secondary);
  font-size: 0.9rem;
}

/* Responsive */
@media (max-width: 768px) {
  .hero h1 { font-size: 1.5rem; }
  .hero .intro { font-size: 1rem; }
  section h2 { font-size: 1.5rem; }
  .video-grid { grid-template-columns: 1fr; }
  .detail-page article { padding: 1.5rem; }
  .detail-page h1 { font-size: 1.75rem; }
  main { padding: 1rem 0.5rem; }
}