:root {
    --primary-color: #6C5CE7;
    --secondary-color: #00D2D3;
    --text-color: #2c3e50;
    --bg-color: #fff;
    --gray-bg: #f8f9fa;
    --border-color: #eee;
    --shadow-sm: 0 2px 10px rgba(0,0,0,0.1);
    --shadow-lg: 0 20px 40px rgba(0,0,0,0.2);
    --navbar-height: 60px;
  }
  
  * {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
  }
  
  body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
    color: var(--text-color);
    line-height: 1.6;
    background: var(--bg-color);
  }
  
  .container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
  }
  
  /* 导航栏 */
  .navbar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    height: var(--navbar-height);
    background: rgba(var(--bg-color), 0.95);
    backdrop-filter: blur(10px);
    box-shadow: var(--shadow-sm);
    z-index: 1000;
  }
  
  .navbar .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    height: 100%;
  }
  
  .navbar-brand {
    font-size: 1.5em;
    font-weight: bold;
    color: var(--primary-color);
    text-decoration: none;
  }
  
  .navbar-links a {
    color: var(--text-color);
    text-decoration: none;
    margin-left: 20px;
    opacity: 0.8;
    transition: opacity 0.3s;
  }
  
  .navbar-links a:hover {
    opacity: 1;
  }
  
  /* 页脚 */
  .footer {
    padding: 40px 0;
    background: var(--gray-bg);
    text-align: center;
  }
  
  .footer-links {
    margin-top: 20px;
  }
  
  .footer-links a {
    color: var(--text-color);
    text-decoration: none;
    margin: 0 10px;
    opacity: 0.8;
  }
  
  /* 工具类 */
  .back-to-top {
    position: fixed;
    right: 20px;
    bottom: 20px;
    width: 40px;
    height: 40px;
    border-radius: 50%;
    background: var(--primary-color);
    color: white;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    opacity: 0;
    transition: opacity 0.3s;
    box-shadow: var(--shadow-sm);
    z-index: 1000;
  }
  
  .back-to-top.visible {
    opacity: 1;
  }
  
  .page-loader {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 3px;
    background: var(--primary-color);
    transform: scaleX(0);
    transform-origin: left;
    transition: transform 0.3s;
    z-index: 1001;
  }
  
  .page-loader.loading {
    transform: scaleX(1);
  }
  
  /* 移动端适配 */
  .menu-toggle {
    display: none;
    font-size: 24px;
    cursor: pointer;
  }
  
  @media (max-width: 768px) {
    .menu-toggle {
      display: block;
    }
  
    .navbar-links {
      display: none;
      position: absolute;
      top: 100%;
      left: 0;
      right: 0;
      background: var(--bg-color);
      padding: 20px;
      box-shadow: var(--shadow-sm);
    }
  
    .navbar-links.active {
      display: flex;
      flex-direction: column;
    }
  
    .navbar-links a {
      margin: 10px 0;
    }
  }