/* 增强样式 */

body {
  min-height: 100vh;
}

.header {
  border-bottom: 1px solid #eee;
}

.logo {
  cursor: pointer;
  user-select: none;
}

.logo:hover {
  color: #b71c1c;
}

.nav a {
  position: relative;
  font-size: 14px;
  font-weight: 500;
}

.nav a::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 50%;
  width: 0;
  height: 2px;
  background: #d32f2f;
  transition: width 0.3s, left 0.3s;
}

.nav a:hover::after {
  width: 100%;
  left: 0;
}

.section {
  animation: fadeIn 0.5s ease-in;
}

@keyframes fadeIn {
  from {
    opacity: 0;
    transform: translateY(10px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.video-card,
.video-item {
  border: 1px solid #eee;
  position: relative;
  overflow: hidden;
}

.video-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: -100%;
  width: 100%;
  height: 100%;
  background: linear-gradient(90deg, transparent, rgba(255,255,255,0.3), transparent);
  transition: left 0.5s;
}

.video-card:hover::before {
  left: 100%;
}

.btn {
  cursor: pointer;
  font-weight: 500;
  letter-spacing: 0.5px;
  box-shadow: 0 2px 4px rgba(211,47,47,0.2);
}

.btn:active {
  transform: scale(0.98);
}

h1,
h2 {
  font-weight: 600;
}

.intro-text {
  text-align: justify;
}

/* 移动端优化 */
@media (max-width: 768px) {
  .header-inner {
    height: 56px;
    padding: 0 12px;
  }

  .logo {
    font-size: 20px;
  }

  .section {
    margin-bottom: 15px;
  }

  h2 {
    font-size: 20px;
  }
}

/* 深色模式支持 */
@media (prefers-color-scheme: dark) {
  body {
    background: #1a1a1a;
    color: #e0e0e0;
  }

  .header {
    background: #2a2a2a;
    box-shadow: 0 2px 8px rgba(0,0,0,0.3);
  }

  .section {
    background: #2a2a2a;
    box-shadow: 0 2px 4px rgba(0,0,0,0.2);
  }

  .video-card,
  .video-item {
    background: #333;
    border-color: #444;
  }

  h1,
  h2,
  .video-title {
    color: #f0f0f0;
  }

  .intro-text,
  .video-desc {
    color: #c0c0c0;
  }

  .video-meta {
    color: #999;
  }
}