* {
  box-sizing: border-box;
}

body {
  margin: 0;
  padding: 0;
  line-height: 1.6;
}

header {
  position: sticky;
  top: 0;
  z-index: 1000;
  background: #fff;
  box-shadow: 0 2px 8px rgba(0,0,0,0.1);
}

.logo {
  text-align: center;
  font-size: 24px;
  font-weight: bold;
  padding: 20px;
  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  color: white;
}

.logo a {
  color: white;
  text-decoration: none;
}

nav {
  display: flex;
  flex-wrap: nowrap !important;
  justify-content: space-between;
  align-items: center;
  overflow-x: visible !important;
}

nav a {
  flex: 1 1 0;
  min-width: 0;
  text-align: center;
  padding: 15px 10px;
  text-decoration: none;
  color: #333;
  font-weight: 500;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
  transition: all 0.3s ease;
  border-bottom: 3px solid transparent;
}

nav a:hover {
  background: #f8f9fa;
  border-bottom-color: #667eea;
  color: #667eea;
}

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

section {
  margin-bottom: 40px;
  background: white;
  padding: 30px;
  border-radius: 8px;
  box-shadow: 0 2px 4px rgba(0,0,0,0.05);
}

h1 {
  font-size: 28px;
  color: #2c3e50;
  margin: 0 0 15px 0;
  line-height: 1.3;
}

h2 {
  font-size: 22px;
  color: #34495e;
  margin: 0 0 20px 0;
  padding-bottom: 10px;
  border-bottom: 2px solid #e0e0e0;
}

h3 {
  font-size: 18px;
  margin: 0 0 8px 0;
}

.hero {
  text-align: center;
  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  color: white;
  padding: 50px 30px;
}

.hero h1 {
  color: white;
  font-size: 32px;
  margin-bottom: 15px;
}

.intro {
  font-size: 16px;
  line-height: 1.8;
  opacity: 0.95;
}

.video-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 20px;
  margin-bottom: 20px;
}

.video-card {
  padding: 20px;
  background: #f8f9fa;
  border-radius: 6px;
  transition: transform 0.2s, box-shadow 0.2s;
}

.video-card:hover {
  transform: translateY(-4px);
  box-shadow: 0 4px 12px rgba(0,0,0,0.1);
}

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

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

.meta {
  color: #7f8c8d;
  font-size: 14px;
  margin: 8px 0;
}

.oneline {
  color: #555;
  font-size: 14px;
  line-height: 1.6;
}

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

.link-card {
  display: block;
  padding: 25px;
  background: linear-gradient(135deg, #f5f7fa 0%, #c3cfe2 100%);
  border-radius: 8px;
  text-decoration: none;
  color: #2c3e50;
  transition: transform 0.2s;
}

.link-card:hover {
  transform: translateY(-3px);
}

.link-card h3 {
  color: #34495e;
  margin-bottom: 10px;
}

.link-card p {
  color: #7f8c8d;
  font-size: 14px;
  margin: 0;
}

.video-list {
  display: flex;
  flex-direction: column;
  gap: 15px;
}

.video-item {
  padding: 15px;
  background: #f8f9fa;
  border-left: 4px solid #667eea;
  border-radius: 4px;
}

.video-item h3 {
  margin: 0 0 8px 0;
}

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

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

.summary {
  color: #555;
  font-size: 14px;
  line-height: 1.6;
  margin: 8px 0 0 0;
}

.more-link {
  text-align: center;
  margin-top: 25px;
}

.more-link a {
  display: inline-block;
  padding: 12px 30px;
  background: #667eea;
  color: white;
  text-decoration: none;
  border-radius: 25px;
  transition: background 0.3s;
}

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

.page-header {
  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  color: white;
}

.page-header h1 {
  color: white;
}

.page-header p {
  opacity: 0.95;
}

.video-list-full {
  display: flex;
  flex-direction: column;
  gap: 20px;
}

.video-item-full {
  position: relative;
  padding: 20px;
  background: #f8f9fa;
  border-radius: 6px;
  border-left: 4px solid #667eea;
}

.rank {
  position: absolute;
  top: 10px;
  right: 10px;
  background: #667eea;
  color: white;
  padding: 5px 12px;
  border-radius: 15px;
  font-weight: bold;
  font-size: 14px;
}

.date {
  display: inline-block;
  background: #95a5a6;
  color: white;
  padding: 3px 10px;
  border-radius: 12px;
  font-size: 12px;
  margin-bottom: 8px;
}

.tags {
  color: #7f8c8d;
  font-size: 13px;
  margin: 5px 0;
}

.detail-header {
  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  color: white;
  padding: 40px;
  border-radius: 8px;
  margin-bottom: 30px;
}

.detail-header h1 {
  color: white;
  font-size: 32px;
  margin: 0;
}

.detail-info dl {
  display: grid;
  grid-template-columns: 120px 1fr;
  gap: 15px;
  margin: 0;
}

.detail-info dt {
  font-weight: bold;
  color: #34495e;
}

.detail-info dd {
  margin: 0;
  color: #555;
}

.highlight {
  font-size: 18px;
  color: #667eea;
  font-weight: 500;
  line-height: 1.8;
  padding: 20px;
  background: #f0f3ff;
  border-radius: 6px;
}

.detail-summary p,
.detail-review p {
  line-height: 1.8;
  color: #444;
  font-size: 15px;
}

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

.related-card {
  padding: 15px;
  background: #f8f9fa;
  border-radius: 6px;
  transition: transform 0.2s;
}

.related-card:hover {
  transform: translateY(-2px);
  box-shadow: 0 4px 8px rgba(0,0,0,0.1);
}

.related-card h3 {
  font-size: 16px;
  margin: 0 0 8px 0;
}

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

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

.related-card .desc {
  font-size: 13px;
  color: #666;
  line-height: 1.5;
  margin: 8px 0 0 0;
}

footer {
  background: #2c3e50;
  color: white;
  text-align: center;
  padding: 30px 20px;
  margin-top: 50px;
}

footer p {
  margin: 0;
  opacity: 0.8;
}

@media (max-width: 768px) {
  nav a {
    padding: 12px 5px;
    font-size: 13px;
  }

  .logo {
    font-size: 20px;
    padding: 15px;
  }

  main {
    padding: 15px;
  }

  section {
    padding: 20px 15px;
  }

  .hero {
    padding: 30px 20px;
  }

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

  h1 {
    font-size: 22px;
  }

  h2 {
    font-size: 18px;
  }

  .video-grid {
    grid-template-columns: 1fr;
    gap: 15px;
  }

  .detail-info dl {
    grid-template-columns: 80px 1fr;
    gap: 10px;
  }

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

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