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

.hero {
  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  color: white;
  padding: 60px 40px;
  border-radius: 12px;
  margin-bottom: 40px;
  text-align: center;
}

.hero h1 {
  font-size: 32px;
  margin-bottom: 20px;
  font-weight: 700;
}

.site-intro {
  max-width: 900px;
  margin: 0 auto;
  font-size: 16px;
  line-height: 1.8;
  opacity: 0.95;
}

section {
  margin-bottom: 50px;
}

section h2 {
  font-size: 26px;
  margin-bottom: 10px;
  color: #1f2937;
  border-left: 4px solid #2563eb;
  padding-left: 15px;
}

.section-desc {
  color: #6b7280;
  margin-bottom: 25px;
  padding-left: 19px;
}

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

.video-card {
  background: white;
  border-radius: 8px;
  padding: 20px;
  box-shadow: 0 2px 8px rgba(0,0,0,0.08);
  transition: all 0.3s ease;
  position: relative;
}

.video-card:hover {
  box-shadow: 0 8px 24px rgba(0,0,0,0.15);
  transform: translateY(-4px);
}

.video-card h3 {
  font-size: 18px;
  margin-bottom: 12px;
  color: #1f2937;
}

.video-card h3 a {
  color: #1f2937;
}

.video-card h3 a:hover {
  color: #2563eb;
  text-decoration: none;
}

.video-meta {
  display: flex;
  gap: 10px;
  flex-wrap: wrap;
  margin-bottom: 12px;
  font-size: 13px;
}

.video-meta span {
  background: #f3f4f6;
  padding: 3px 10px;
  border-radius: 4px;
  color: #6b7280;
}

.video-desc {
  color: #4b5563;
  font-size: 14px;
  line-height: 1.6;
  margin-bottom: 10px;
}

.video-tags {
  color: #9ca3af;
  font-size: 12px;
}

.card-index {
  position: absolute;
  top: 15px;
  right: 15px;
  background: #2563eb;
  color: white;
  width: 32px;
  height: 32px;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: bold;
  font-size: 14px;
}

.section-links {
  margin-top: 30px;
  padding-left: 19px;
}

.section-links a {
  color: #2563eb;
  font-size: 16px;
  margin-right: 20px;
}

.section-links .divider {
  color: #d1d5db;
  margin-right: 20px;
}

.page-header {
  background: white;
  padding: 40px;
  border-radius: 12px;
  margin-bottom: 40px;
  box-shadow: 0 2px 8px rgba(0,0,0,0.08);
}

.page-header h1 {
  font-size: 32px;
  margin-bottom: 15px;
  color: #1f2937;
}

.page-header p {
  color: #6b7280;
  font-size: 15px;
  line-height: 1.8;
}

.video-detail {
  background: white;
  padding: 40px;
  border-radius: 12px;
  box-shadow: 0 2px 8px rgba(0,0,0,0.08);
}

.video-detail header {
  border-bottom: 2px solid #e5e7eb;
  padding-bottom: 25px;
  margin-bottom: 30px;
}

.video-detail h1 {
  font-size: 36px;
  margin-bottom: 10px;
  color: #1f2937;
}

.subtitle {
  color: #6b7280;
  font-size: 16px;
}

.detail-info,
.detail-oneline,
.detail-summary,
.detail-review,
.detail-related {
  margin-bottom: 35px;
}

.detail-info h2,
.detail-oneline h2,
.detail-summary h2,
.detail-review h2,
.detail-related h2 {
  font-size: 22px;
  margin-bottom: 18px;
  color: #1f2937;
  border-left: 4px solid #2563eb;
  padding-left: 12px;
}

.detail-info dl {
  display: grid;
  grid-template-columns: 80px 1fr;
  gap: 12px 20px;
  font-size: 15px;
}

.detail-info dt {
  color: #6b7280;
  font-weight: 600;
}

.detail-info dd {
  color: #1f2937;
}

.detail-oneline p,
.detail-summary p,
.detail-review p {
  color: #4b5563;
  font-size: 16px;
  line-height: 1.9;
  text-align: justify;
}

.detail-summary p {
  text-indent: 2em;
}

.site-footer {
  background: #1f2937;
  color: #9ca3af;
  text-align: center;
  padding: 30px 20px;
  margin-top: 60px;
}

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

  .hero {
    padding: 40px 25px;
  }

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

  .site-intro {
    font-size: 14px;
  }

  section h2 {
    font-size: 22px;
  }

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

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

  .video-detail h1 {
    font-size: 28px;
  }

  .detail-info dl {
    grid-template-columns: 70px 1fr;
    gap: 10px 15px;
    font-size: 14px;
  }
}