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

header {
  background: white;
  box-shadow: 0 2px 4px rgba(0,0,0,0.05);
  margin-bottom: 30px;
}

.hero {
  text-align: center;
  padding: 60px 20px 40px;
  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  color: white;
}

.logo {
  font-size: 28px;
  font-weight: 700;
  margin-bottom: 15px;
  letter-spacing: 2px;
}

.hero h1 {
  font-size: 32px;
  font-weight: 700;
  line-height: 1.4;
  max-width: 900px;
  margin: 0 auto;
}

.page-header {
  text-align: center;
  padding: 40px 20px 30px;
  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  color: white;
}

.page-header .logo {
  font-size: 24px;
  margin-bottom: 10px;
}

.page-header h1 {
  font-size: 28px;
  font-weight: 700;
  margin-bottom: 10px;
}

.page-header .subtitle {
  font-size: 16px;
  opacity: 0.95;
}

.intro {
  background: white;
  padding: 30px;
  border-radius: 12px;
  margin-bottom: 40px;
  box-shadow: 0 2px 8px rgba(0,0,0,0.05);
  line-height: 1.8;
}

.intro p {
  font-size: 16px;
  color: #555;
}

section {
  margin-bottom: 50px;
}

section h2 {
  font-size: 26px;
  margin-bottom: 25px;
  color: #333;
  border-left: 4px solid #667eea;
  padding-left: 15px;
}

.video-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 25px;
}

.video-card {
  background: white;
  border-radius: 12px;
  padding: 25px;
  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 8px 20px rgba(0,0,0,0.12);
}

.video-card h3 {
  font-size: 18px;
  margin-bottom: 10px;
  color: #333;
}

.video-card h3 a {
  color: #333;
}

.video-card h3 a:hover {
  color: #667eea;
}

.meta {
  font-size: 13px;
  color: #888;
  margin-bottom: 10px;
}

.desc {
  font-size: 14px;
  color: #666;
  line-height: 1.6;
  margin-bottom: 12px;
}

.tags {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
}

.tags span, .tag {
  display: inline-block;
  background: #f0f0f0;
  padding: 4px 10px;
  border-radius: 4px;
  font-size: 12px;
  color: #666;
}

.review {
  font-size: 14px;
  color: #555;
  font-style: italic;
  margin-top: 10px;
  padding-top: 10px;
  border-top: 1px solid #eee;
}

.video-list {
  background: white;
  border-radius: 12px;
  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: 8px;
}

.video-item h3 a {
  color: #333;
}

.video-item h3 a:hover {
  color: #667eea;
}

.video-item p {
  font-size: 14px;
  color: #666;
  line-height: 1.6;
}

.ranked-list {
  background: white;
  border-radius: 12px;
  padding: 20px;
  box-shadow: 0 2px 8px rgba(0,0,0,0.05);
}

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

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

.rank-num {
  font-size: 28px;
  font-weight: 700;
  color: #667eea;
  min-width: 50px;
  text-align: center;
}

.rank-content {
  flex: 1;
}

.rank-content h3 {
  font-size: 18px;
  margin-bottom: 8px;
}

.rank-content h3 a {
  color: #333;
}

.rank-content h3 a:hover {
  color: #667eea;
}

.rank-content p {
  font-size: 14px;
  color: #666;
  line-height: 1.6;
}

.group-section {
  background: white;
  border-radius: 12px;
  padding: 25px;
  margin-bottom: 25px;
  box-shadow: 0 2px 8px rgba(0,0,0,0.05);
}

.group-title {
  font-size: 20px;
  color: #667eea;
  margin-bottom: 20px;
  padding-bottom: 10px;
  border-bottom: 2px solid #f0f0f0;
}

.group-items {
  display: grid;
  gap: 15px;
}

.group-item {
  padding: 15px;
  background: #fafafa;
  border-radius: 8px;
  transition: background 0.3s;
}

.group-item:hover {
  background: #f0f0f0;
}

.group-item h4 {
  font-size: 16px;
  margin-bottom: 6px;
}

.group-item h4 a {
  color: #333;
}

.group-item h4 a:hover {
  color: #667eea;
}

.group-item p {
  font-size: 14px;
  color: #666;
}

.item-date {
  font-size: 13px;
  color: #888;
  margin-bottom: 8px;
  font-weight: 600;
}

.item-content {
  padding-left: 15px;
  border-left: 3px solid #667eea;
}

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

.more-link a {
  display: inline-block;
  padding: 12px 30px;
  background: #667eea;
  color: white;
  border-radius: 25px;
  font-weight: 500;
  transition: background 0.3s;
}

.more-link a:hover {
  background: #5568d3;
}

.rank-intro {
  background: white;
  padding: 20px;
  border-radius: 12px;
  margin-bottom: 25px;
  box-shadow: 0 2px 8px rgba(0,0,0,0.05);
}

.rank-intro p {
  font-size: 15px;
  color: #666;
  line-height: 1.7;
}

.quick-links {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 25px;
  margin-bottom: 30px;
}

.quick-link-card {
  background: white;
  padding: 30px;
  border-radius: 12px;
  box-shadow: 0 2px 8px rgba(0,0,0,0.08);
  transition: transform 0.3s, box-shadow 0.3s;
  display: block;
  color: inherit;
}

.quick-link-card:hover {
  transform: translateY(-4px);
  box-shadow: 0 8px 20px rgba(0,0,0,0.12);
}

.quick-link-card h3 {
  font-size: 20px;
  color: #667eea;
  margin-bottom: 10px;
}

.quick-link-card p {
  font-size: 14px;
  color: #666;
}

.detail-page {
  max-width: 900px;
}

.video-detail {
  background: white;
  padding: 40px;
  border-radius: 12px;
  box-shadow: 0 2px 8px rgba(0,0,0,0.05);
}

.video-detail h1 {
  font-size: 32px;
  color: #333;
  margin-bottom: 30px;
  padding-bottom: 20px;
  border-bottom: 3px solid #667eea;
}

.basic-info {
  background: #f8f9fa;
  padding: 25px;
  border-radius: 8px;
  margin-bottom: 30px;
}

.info-row {
  padding: 10px 0;
  font-size: 15px;
  line-height: 1.6;
  border-bottom: 1px solid #e9ecef;
}

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

.info-row strong {
  color: #555;
  min-width: 80px;
  display: inline-block;
}

.highlight {
  background: linear-gradient(135deg, #667eea15 0%, #764ba215 100%);
  padding: 25px;
  border-radius: 8px;
  margin-bottom: 30px;
}

.highlight h2 {
  font-size: 20px;
  color: #667eea;
  margin-bottom: 15px;
  border: none;
  padding: 0;
}

.one-line {
  font-size: 18px;
  color: #333;
  font-weight: 500;
  line-height: 1.6;
}

.summary, .review {
  margin-bottom: 30px;
}

.summary h2, .review h2, .related h2 {
  font-size: 22px;
  color: #333;
  margin-bottom: 15px;
  border-left: 4px solid #667eea;
  padding-left: 15px;
}

.summary p, .review p {
  font-size: 16px;
  color: #555;
  line-height: 1.8;
  text-align: justify;
}

.related {
  margin-top: 40px;
  padding-top: 30px;
  border-top: 2px solid #f0f0f0;
}

.related-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(250px, 1fr));
  gap: 20px;
}

.related-card {
  background: #f8f9fa;
  padding: 20px;
  border-radius: 8px;
  transition: background 0.3s;
}

.related-card:hover {
  background: #e9ecef;
}

.related-card h3 {
  font-size: 16px;
  margin-bottom: 10px;
}

.related-card h3 a {
  color: #333;
}

.related-card h3 a:hover {
  color: #667eea;
}

.related-desc {
  font-size: 14px;
  color: #666;
  margin-bottom: 8px;
  line-height: 1.5;
}

.related-meta {
  font-size: 12px;
  color: #888;
}

footer {
  background: #333;
  color: white;
  text-align: center;
  padding: 30px 20px;
  margin-top: 60px;
}

footer p {
  font-size: 14px;
  opacity: 0.9;
}

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

  .hero {
    padding: 40px 15px 30px;
  }

  .logo {
    font-size: 22px;
  }

  .hero h1 {
    font-size: 24px;
  }

  .page-header h1 {
    font-size: 22px;
  }

  section h2 {
    font-size: 22px;
  }

  .video-grid {
    grid-template-columns: 1fr;
    gap: 20px;
  }

  .video-detail {
    padding: 25px 20px;
  }

  .video-detail h1 {
    font-size: 24px;
  }

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

  .quick-links {
    grid-template-columns: 1fr;
  }

  .ranked-item {
    gap: 15px;
  }

  .rank-num {
    font-size: 22px;
    min-width: 40px;
  }
}