/* Base Styles */
body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, "Noto Sans", sans-serif;
  line-height: 1.6;
  color: #333;
  background: #f8f9fa;
}

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

/* Header */
header {
  background: linear-gradient(135deg, #2c3e50 0%, #3498db 100%);
  color: white;
  padding: 1.5rem 0;
  box-shadow: 0 2px 10px rgba(0,0,0,0.1);
}

header h1 {
  font-size: 1.8rem;
  margin-bottom: 1rem;
  font-weight: 600;
}

header h1 a {
  color: white;
  text-decoration: none;
}

header h1 a:hover {
  opacity: 0.9;
}

nav ul {
  list-style: none;
  display: flex;
  flex-wrap: nowrap;
  justify-content: space-between;
  align-items: center;
  gap: 0.5rem;
  padding: 0;
}

nav li {
  flex: 1 1 0;
  min-width: 0;
  text-align: center;
}

nav a {
  color: white;
  text-decoration: none;
  padding: 0.6rem 0.5rem;
  display: block;
  border-radius: 4px;
  transition: all 0.3s ease;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
  font-size: 0.95rem;
}

nav a:hover {
  background: rgba(255, 255, 255, 0.2);
  transform: translateY(-2px);
}

@media (max-width: 768px) {
  nav a {
    font-size: 0.85rem;
    padding: 0.5rem 0.25rem;
  }
}

/* Main Content */
main {
  min-height: 60vh;
  padding: 2rem 0;
}

h1 {
  color: #2c3e50;
  margin-bottom: 1.5rem;
  font-size: 2rem;
  font-weight: 700;
}

h2 {
  color: #34495e;
  margin: 2rem 0 1rem;
  font-size: 1.5rem;
  font-weight: 600;
  border-left: 4px solid #3498db;
  padding-left: 1rem;
}

h3 {
  color: #2c3e50;
  font-size: 1.2rem;
  margin-bottom: 0.5rem;
}

section {
  background: white;
  padding: 2rem;
  margin-bottom: 2rem;
  border-radius: 8px;
  box-shadow: 0 2px 8px rgba(0,0,0,0.08);
}

.hero h1 {
  text-align: center;
  color: #2c3e50;
  font-size: 2.2rem;
  padding: 1rem 0;
}

.intro, .site-intro {
  line-height: 1.8;
  font-size: 1.05rem;
}

.intro p, .site-intro p {
  margin-bottom: 1rem;
}

.intro a, .site-intro a {
  color: #3498db;
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: border-color 0.3s;
}

.intro a:hover, .site-intro a:hover {
  border-bottom-color: #3498db;
}

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

.video-card {
  background: #f8f9fa;
  padding: 1.5rem;
  border-radius: 8px;
  transition: all 0.3s ease;
  border: 1px solid #e9ecef;
}

.video-card:hover {
  transform: translateY(-4px);
  box-shadow: 0 4px 12px rgba(0,0,0,0.15);
  border-color: #3498db;
}

.video-card h3 {
  margin-bottom: 0.8rem;
}

.video-card h3 a {
  color: #2c3e50;
  text-decoration: none;
  font-weight: 600;
}

.video-card h3 a:hover {
  color: #3498db;
}

.video-card .meta {
  color: #7f8c8d;
  font-size: 0.9rem;
  margin-bottom: 0.5rem;
}

.video-card .tags {
  color: #95a5a6;
  font-size: 0.85rem;
  margin-bottom: 0.5rem;
}

.video-card .summary, .video-card .genre {
  color: #555;
  font-size: 0.95rem;
  line-height: 1.5;
}

/* Video List */
.video-list {
  display: flex;
  flex-direction: column;
  gap: 1rem;
  margin-top: 1.5rem;
}

.video-item {
  background: #f8f9fa;
  padding: 1.25rem;
  border-radius: 6px;
  border-left: 3px solid #3498db;
  transition: all 0.3s ease;
}

.video-item:hover {
  background: #e9ecef;
  transform: translateX(4px);
}

.video-item h3 {
  margin-bottom: 0.5rem;
}

.video-item h3 a {
  color: #2c3e50;
  text-decoration: none;
  font-weight: 600;
}

.video-item h3 a:hover {
  color: #3498db;
}

.video-item .meta {
  color: #7f8c8d;
  font-size: 0.9rem;
  margin-bottom: 0.4rem;
}

.video-item .desc {
  color: #555;
  font-size: 0.95rem;
}

/* List Entries */
.list-entries {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 1.5rem;
  margin-top: 1.5rem;
}

.list-entry {
  background: #f8f9fa;
  padding: 1.5rem;
  border-radius: 8px;
  border: 1px solid #e9ecef;
  transition: all 0.3s ease;
}

.list-entry:hover {
  border-color: #3498db;
  box-shadow: 0 4px 12px rgba(0,0,0,0.1);
}

.list-entry h3 a {
  color: #2c3e50;
  text-decoration: none;
  font-weight: 600;
}

.list-entry h3 a:hover {
  color: #3498db;
}

.list-entry p {
  color: #555;
  margin-top: 0.8rem;
  line-height: 1.6;
}

/* Top List */
.top-list {
  margin-top: 1.5rem;
}

.top-item {
  display: flex;
  gap: 1.5rem;
  background: #f8f9fa;
  padding: 1.5rem;
  margin-bottom: 1rem;
  border-radius: 8px;
  border: 1px solid #e9ecef;
  transition: all 0.3s ease;
}

.top-item:hover {
  border-color: #3498db;
  box-shadow: 0 4px 12px rgba(0,0,0,0.1);
}

.rank {
  flex-shrink: 0;
}

.rank-number {
  display: inline-block;
  width: 3rem;
  height: 3rem;
  line-height: 3rem;
  text-align: center;
  background: linear-gradient(135deg, #3498db, #2c3e50);
  color: white;
  font-size: 1.5rem;
  font-weight: 700;
  border-radius: 50%;
}

.top-content {
  flex: 1;
}

.top-content h3 {
  margin-bottom: 0.6rem;
}

.top-content h3 a {
  color: #2c3e50;
  text-decoration: none;
  font-weight: 600;
  font-size: 1.25rem;
}

.top-content h3 a:hover {
  color: #3498db;
}

.top-content .meta {
  color: #7f8c8d;
  font-size: 0.9rem;
  margin-bottom: 0.4rem;
}

.top-content .tags {
  color: #95a5a6;
  font-size: 0.85rem;
  margin-bottom: 0.6rem;
}

.top-content .recommendation {
  color: #555;
  line-height: 1.7;
  font-size: 1rem;
}

/* Topic Page */
.topic-intro {
  line-height: 1.9;
  font-size: 1.05rem;
}

.topic-intro p {
  margin-bottom: 1.2rem;
}

.topic-list {
  margin-top: 1.5rem;
}

.topic-item {
  background: #f8f9fa;
  padding: 1.8rem;
  margin-bottom: 1.5rem;
  border-radius: 8px;
  border: 1px solid #e9ecef;
  transition: all 0.3s ease;
}

.topic-item:hover {
  border-color: #3498db;
  box-shadow: 0 4px 12px rgba(0,0,0,0.1);
}

.topic-item h3 a {
  color: #2c3e50;
  text-decoration: none;
  font-weight: 600;
  font-size: 1.3rem;
}

.topic-item h3 a:hover {
  color: #3498db;
}

.topic-item .meta {
  color: #7f8c8d;
  font-size: 0.9rem;
  margin: 0.6rem 0;
}

.topic-desc {
  color: #555;
  line-height: 1.8;
  font-size: 1rem;
}

.topic-desc p {
  margin-bottom: 1rem;
}

.topic-reason {
  background: #e8f4f8;
  padding: 1rem;
  border-left: 3px solid #3498db;
  margin-top: 1rem;
  font-style: italic;
}

/* Latest List */
.latest-list {
  margin-top: 1.5rem;
}

.latest-item {
  display: flex;
  gap: 1.5rem;
  background: #f8f9fa;
  padding: 1.25rem;
  margin-bottom: 1rem;
  border-radius: 6px;
  border: 1px solid #e9ecef;
  transition: all 0.3s ease;
}

.latest-item:hover {
  border-color: #3498db;
  box-shadow: 0 4px 12px rgba(0,0,0,0.1);
}

.latest-date {
  flex-shrink: 0;
  display: flex;
  align-items: center;
}

.latest-date span {
  display: inline-block;
  padding: 0.5rem 0.8rem;
  background: #3498db;
  color: white;
  border-radius: 4px;
  font-size: 0.9rem;
  font-weight: 600;
}

.latest-content {
  flex: 1;
}

.latest-content h3 {
  margin-bottom: 0.5rem;
}

.latest-content h3 a {
  color: #2c3e50;
  text-decoration: none;
  font-weight: 600;
}

.latest-content h3 a:hover {
  color: #3498db;
}

.latest-content .meta {
  color: #7f8c8d;
  font-size: 0.9rem;
  margin-bottom: 0.4rem;
}

.latest-content .brief {
  color: #555;
  font-size: 0.95rem;
}

/* Year Group */
.year-group {
  margin-bottom: 3rem;
}

.year-group h2 {
  color: #2c3e50;
  font-size: 1.6rem;
  margin-bottom: 1.5rem;
  padding-bottom: 0.5rem;
  border-bottom: 2px solid #3498db;
}

/* Detail Page */
.detail {
  background: white;
  padding: 2rem;
  border-radius: 8px;
  box-shadow: 0 2px 8px rgba(0,0,0,0.08);
}

.detail h1 {
  color: #2c3e50;
  margin-bottom: 2rem;
  padding-bottom: 1rem;
  border-bottom: 3px solid #3498db;
}

.basic-info dl {
  display: grid;
  grid-template-columns: 120px 1fr;
  gap: 0.8rem 1.5rem;
  margin-top: 1rem;
}

.basic-info dt {
  font-weight: 600;
  color: #555;
}

.basic-info dd {
  color: #333;
  margin: 0;
}

.highlight {
  background: linear-gradient(135deg, #e8f4f8 0%, #d4ebf7 100%);
  padding: 2rem;
  border-radius: 8px;
  border-left: 4px solid #3498db;
}

.one-line {
  font-size: 1.2rem;
  font-weight: 500;
  color: #2c3e50;
  line-height: 1.8;
}

.summary p, .review p {
  line-height: 1.9;
  font-size: 1.05rem;
  color: #444;
  text-align: justify;
}

.review {
  background: #fff8e6;
  border-left: 4px solid #f39c12;
}

.related-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(250px, 1fr));
  gap: 1.5rem;
  margin-top: 1.5rem;
}

.related-card {
  background: #f8f9fa;
  padding: 1.25rem;
  border-radius: 6px;
  border: 1px solid #e9ecef;
  transition: all 0.3s ease;
}

.related-card:hover {
  border-color: #3498db;
  box-shadow: 0 4px 12px rgba(0,0,0,0.1);
  transform: translateY(-2px);
}

.related-card h3 {
  margin-bottom: 0.6rem;
  font-size: 1.1rem;
}

.related-card h3 a {
  color: #2c3e50;
  text-decoration: none;
  font-weight: 600;
}

.related-card h3 a:hover {
  color: #3498db;
}

.related-card .meta {
  color: #7f8c8d;
  font-size: 0.85rem;
  margin-bottom: 0.5rem;
}

.related-card .desc {
  color: #555;
  font-size: 0.9rem;
  line-height: 1.5;
}

/* Footer */
footer {
  background: #2c3e50;
  color: white;
  padding: 2rem 0;
  margin-top: 3rem;
}

.footer-nav {
  display: flex;
  justify-content: center;
  flex-wrap: wrap;
  gap: 1.5rem;
  margin-bottom: 1rem;
}

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

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

footer p {
  text-align: center;
  color: #95a5a6;
  font-size: 0.9rem;
}

/* Responsive */
@media (max-width: 768px) {
  .container {
    padding: 0 0.75rem;
  }

  header h1 {
    font-size: 1.4rem;
  }

  main {
    padding: 1.5rem 0;
  }

  h1 {
    font-size: 1.6rem;
  }

  h2 {
    font-size: 1.3rem;
  }

  section {
    padding: 1.5rem;
  }

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

  .top-item {
    flex-direction: column;
    gap: 1rem;
  }

  .rank-number {
    width: 2.5rem;
    height: 2.5rem;
    line-height: 2.5rem;
    font-size: 1.2rem;
  }

  .latest-item {
    flex-direction: column;
    gap: 0.8rem;
  }

  .basic-info dl {
    grid-template-columns: 100px 1fr;
    gap: 0.6rem 1rem;
  }

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

/* UI Style Variants */
.ui-style-0 { --primary-color: #3498db; }
.ui-style-1 { --primary-color: #2ecc71; }
.ui-style-2 { --primary-color: #e74c3c; }
.ui-style-3 { --primary-color: #f39c12; }
.ui-style-4 { --primary-color: #9b59b6; }
.ui-style-5 { --primary-color: #1abc9c; }
.ui-style-6 { --primary-color: #34495e; }
.ui-style-7 { --primary-color: #16a085; }
.ui-style-8 { --primary-color: #27ae60; }
.ui-style-9 { --primary-color: #2980b9; }
.ui-style-10 { --primary-color: #8e44ad; }
.ui-style-11 { --primary-color: #c0392b; }
.ui-style-12 { --primary-color: #d35400; }
.ui-style-13 { --primary-color: #2c3e50; }
.ui-style-14 { --primary-color: #7f8c8d; }
.ui-style-15 { --primary-color: #17a2b8; }