body {
    font-family: Arial, sans-serif;
    margin: 0;
    padding: 0;
  }
  
  .navbar {
    position: fixed;         /* 固定在页面顶部 */
    top: 0;                  /* 距离顶部为 0 */
    left: 0;
    width: 100%;             /* 宽度铺满 */
    z-index: 1000;           /* 层级高于内容 */
    display: flex;
    justify-content: center;
    align-items: center;
    background: #fff;
    padding: 20px 40px;
    box-shadow: 0 2px 4px rgba(0,0,0,0.1);
    gap: 30px;
  }
  
  
  .logo {
    height: 50px;
    margin-right: 0;  /* ❌ 去掉原 margin-right: 30px，使用 gap 控制间距 */
  }
  
  .nav-links {
    list-style: none;
    display: flex;
    gap: 20px;
    padding: 0;
    margin: 0;
  }
  
  .nav-links li a {
    text-decoration: none;
    color: #555;
    font-weight: 500;
    font-size: 19px; /* ✅ 字体大小改这里，例如18px */
  }
  
  .nav-links li a.active,
  .nav-links li a:hover {
    color: #000;
    font-weight: bold;
  }
  
  main {
    padding: 100px 20px 20px;  /* 顶部留出空位，避免被导航遮住 */
  }
  
  .carousel-container {
    position: relative;
    max-width: 100%;
    height: 650px;  /* ✅ 拉高，比如 600px 或你想要的值 */
    overflow: hidden;
    margin: 0 auto;
  }
  
  .carousel-slide {
    display: none;
    width: 100%;
    height: 100%;
  }
  
  .carousel-slide img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    border-radius: 0;
  }
  
  .fade {
    animation: fadeEffect 1s ease-in-out;
  }
  
  @keyframes fadeEffect {
    from { opacity: 0.4; }
    to { opacity: 1; }
  }