/* UI Style: 0, Layout: E */
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "Roboto", "Helvetica Neue", Arial, sans-serif;
  line-height: 1.6;
  color: #333;
  background: #f5f5f5;
}

a {
  color: #0066cc;
  text-decoration: none;
}

a:hover {
  color: #004499;
  text-decoration: underline;
}

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

header {
  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  color: white;
  padding: 20px 0;
  box-shadow: 0 2px 10px rgba(0,0,0,0.1);
}

.header-content {
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 15px;
}

.logo {
  font-size: 28px;
  font-weight: bold;
  color: white;
  text-decoration: none;
}

nav ul {
  display: flex;
  list-style: none;
  gap: 20px;
  flex-wrap: nowrap;
}

nav a {
  color: white;
  font-weight: 500;
  white-space: nowrap;
}

nav a:hover {
  color: #ffd700;
  text-decoration: none;
}

main {
  padding: 30px 0;
}

.intro-section {
  background: white;
  padding: 30px;
  margin-bottom: 30px;
  border-radius: 8px;
  box-shadow: 0 2px 8px rgba(0,0,0,0.1);
}

.intro-section h1 {
  font-size: 32px;
  color: #2c3e50;
  margin-bottom: 20px;
}

.intro-section p {
  font-size: 16px;
  line-height: 1.8;
  color: #555;
}

.section {
  background: white;
  padding: 30px;
  margin-bottom: 30px;
  border-radius: 8px;
  box-shadow: 0 2px 8px rgba(0,0,0,0.1);
}

.section h2 {
  font-size: 26px;
  color: #2c3e50;
  margin-bottom: 20px;
  padding-bottom: 10px;
  border-bottom: 3px solid #667eea;
}

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

.video-card {
  background: #f9f9f9;
  padding: 20px;
  border-radius: 8px;
  transition: transform 0.3s, box-shadow 0.3s;
  border: 1px solid #e0e0e0;
}

.video-card:hover {
  transform: translateY(-5px);
  box-shadow: 0 4px 16px rgba(0,0,0,0.15);
}

.video-card h3 {
  font-size: 18px;
  color: #2c3e50;
  margin-bottom: 10px;
}

.video-meta {
  font-size: 14px;
  color: #666;
  margin-bottom: 10px;
}

.video-desc {
  font-size: 14px;
  color: #777;
  line-height: 1.5;
  margin-bottom: 15px;
}

.video-link {
  display: inline-block;
  padding: 8px 16px;
  background: #667eea;
  color: white;
  border-radius: 4px;
  font-weight: 500;
  transition: background 0.3s;
}

.video-link:hover {
  background: #5568d3;
  text-decoration: none;
}

.detail-container {
  background: white;
  padding: 40px;
  border-radius: 8px;
  box-shadow: 0 2px 8px rgba(0,0,0,0.1);
}

.detail-title {
  font-size: 36px;
  color: #2c3e50;
  margin-bottom: 20px;
}

.detail-meta {
  display: flex;
  flex-wrap: wrap;
  gap: 15px;
  padding: 20px;
  background: #f9f9f9;
  border-radius: 8px;
  margin-bottom: 30px;
}

.meta-item {
  font-size: 15px;
  color: #555;
}

.meta-label {
  font-weight: bold;
  color: #333;
}

.detail-section {
  margin-bottom: 30px;
}

.detail-section h2 {
  font-size: 24px;
  color: #2c3e50;
  margin-bottom: 15px;
  padding-bottom: 10px;
  border-bottom: 2px solid #667eea;
}

.detail-section p {
  font-size: 16px;
  line-height: 1.8;
  color: #555;
}

.tags {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: 15px;
}

.tag {
  padding: 6px 12px;
  background: #667eea;
  color: white;
  border-radius: 4px;
  font-size: 14px;
}

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

.related-card {
  background: #f9f9f9;
  padding: 15px;
  border-radius: 8px;
  border: 1px solid #e0e0e0;
}

.related-card h4 {
  font-size: 16px;
  color: #2c3e50;
  margin-bottom: 8px;
}

.related-card p {
  font-size: 14px;
  color: #666;
  margin-bottom: 10px;
}

footer {
  background: #2c3e50;
  color: white;
  padding: 20px 0;
  text-align: center;
  margin-top: 50px;
}

@media (max-width: 768px) {
  .header-content {
    flex-direction: column;
    align-items: flex-start;
  }

  nav ul {
    width: 100%;
    justify-content: space-between;
    flex-wrap: nowrap;
    gap: 0;
    padding: 0;
  }

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

  nav a {
    display: block;
    padding: 8px 4px;
    font-size: 13px;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
  }

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

  .detail-container {
    padding: 20px;
  }

  .detail-title {
    font-size: 28px;
  }

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

@media (max-width: 480px) {
  .logo {
    font-size: 22px;
  }

  nav a {
    font-size: 12px;
    padding: 6px 2px;
  }

  .intro-section h1 {
    font-size: 24px;
  }

  .section h2 {
    font-size: 22px;
  }
}