* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

body.ui-style-7 {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'Microsoft YaHei', sans-serif;
  line-height: 1.6;
  color: #2c3e50;
  background: linear-gradient(135deg, #f5f7fa 0%, #c3cfe2 100%);
  min-height: 100vh;
}

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

header {
  background: rgba(255, 255, 255, 0.95);
  box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
  position: sticky;
  top: 0;
  z-index: 1000;
  backdrop-filter: blur(10px);
}

.header-content {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 15px 0;
  flex-wrap: wrap;
}

.logo {
  font-size: 26px;
  font-weight: 700;
  color: #2c3e50;
  text-decoration: none;
  letter-spacing: 1px;
  transition: color 0.3s;
}

.logo:hover {
  color: #3498db;
}

nav ul {
  list-style: none;
  display: flex;
  flex-wrap: nowrap;
  gap: 5px;
}

nav ul li a {
  color: #34495e;
  text-decoration: none;
  padding: 8px 15px;
  border-radius: 5px;
  transition: all 0.3s;
  font-size: 15px;
  white-space: nowrap;
}

nav ul li a:hover {
  background: #3498db;
  color: white;
}

main {
  padding: 40px 0;
}

h1 {
  font-size: 32px;
  color: #2c3e50;
  margin-bottom: 20px;
  text-align: center;
  line-height: 1.4;
}

h2 {
  font-size: 24px;
  color: #34495e;
  margin: 30px 0 20px;
  padding-bottom: 10px;
  border-bottom: 3px solid #3498db;
}

.intro-section {
  background: white;
  padding: 30px;
  border-radius: 10px;
  box-shadow: 0 4px 15px rgba(0, 0, 0, 0.1);
  margin-bottom: 40px;
  line-height: 1.8;
}

section {
  background: white;
  padding: 30px;
  border-radius: 10px;
  box-shadow: 0 4px 15px rgba(0, 0, 0, 0.1);
  margin-bottom: 30px;
}

.video-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 25px;
  margin-top: 20px;
}

.video-card {
  background: #f8f9fa;
  border-radius: 8px;
  padding: 20px;
  transition: transform 0.3s, box-shadow 0.3s;
  border: 1px solid #e1e8ed;
}

.video-card:hover {
  transform: translateY(-5px);
  box-shadow: 0 8px 20px rgba(0, 0, 0, 0.15);
}

.video-card h3 {
  font-size: 18px;
  color: #2c3e50;
  margin-bottom: 10px;
  line-height: 1.4;
}

.video-card h3 a {
  color: #2c3e50;
  text-decoration: none;
  transition: color 0.3s;
}

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

.video-meta {
  font-size: 13px;
  color: #7f8c8d;
  margin: 8px 0;
}

.video-desc {
  font-size: 14px;
  color: #555;
  line-height: 1.6;
  margin-top: 10px;
}

.video-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  margin-top: 12px;
}

.tag {
  background: #3498db;
  color: white;
  padding: 3px 10px;
  border-radius: 12px;
  font-size: 12px;
}

.video-list {
  list-style: none;
}

.video-list li {
  background: #f8f9fa;
  padding: 20px;
  margin-bottom: 15px;
  border-radius: 8px;
  border-left: 4px solid #3498db;
  transition: all 0.3s;
}

.video-list li:hover {
  background: #e8f4f8;
  transform: translateX(5px);
}

.video-list h3 {
  font-size: 18px;
  margin-bottom: 10px;
}

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

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

.detail-info {
  background: #f8f9fa;
  padding: 20px;
  border-radius: 8px;
  margin: 20px 0;
}

.detail-info p {
  margin: 10px 0;
  line-height: 1.8;
}

.detail-info strong {
  color: #2c3e50;
  min-width: 80px;
  display: inline-block;
}

.related-section {
  margin-top: 40px;
}

footer {
  background: rgba(255, 255, 255, 0.95);
  padding: 30px 0;
  text-align: center;
  color: #7f8c8d;
  margin-top: 50px;
}

@media (max-width: 768px) {
  .header-content {
    justify-content: center;
  }

  .logo {
    font-size: 22px;
    margin-bottom: 10px;
    width: 100%;
    text-align: center;
  }

  nav {
    width: 100%;
  }

  nav ul {
    justify-content: space-between;
    width: 100%;
    flex-wrap: nowrap;
    overflow: hidden;
  }

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

  nav ul li a {
    padding: 8px 5px;
    font-size: 13px;
    display: block;
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
  }

  h1 {
    font-size: 24px;
  }

  h2 {
    font-size: 20px;
  }

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

  .intro-section, section {
    padding: 20px;
  }
}

@media (max-width: 480px) {
  nav ul li a {
    padding: 6px 3px;
    font-size: 12px;
  }

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