/* 全局样式设置 */
  body {
    margin: 0;
    padding: 0;
    font-family: 'Roboto', sans-serif;
    font-size: 16px;
    color: #FFFFFF;
    background: linear-gradient(to bottom, #1E90FF, #87CEEB);
  }

  /* 导航栏样式 */
  nav {
    position: fixed;
    top: 0;
    width: 100%;
    background-color: #0A2540;
    display: flex;
    justify-content: space-around;
    align-items: center;
    padding: 15px 0;
    z-index: 1000;
    box-shadow: 0 2px 4px rgba(0,0,0,0.1);
  }

  nav a {
    color: #FFFFFF;
    text-decoration: none;
    font-size: 18px;
    transition: color 0.3s ease;
  }

  nav a:hover {
    color: #FFA500;
  }

  /* 主内容容器 */
  .container {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 20px;
    padding: 100px 20px 50px 20px;
    max-width: 1200px;
    margin: 0 auto;
  }

  /* 卡片样式 */
  .card {
    background-color: rgba(255, 255, 255, 0.1);
    border-radius: 10px;
    box-shadow: 0 8px 16px rgba(0,0,0,0.2);
    padding: 20px;
    transition: transform 0.3s, box-shadow 0.3s;
    backdrop-filter: blur(10px);
  }

  .card:hover {
    transform: scale(1.05);
    box-shadow: 0 12px 24px rgba(0,0,0,0.3);
  }

  /* 章节标题样式 */
  h2, h3, h4 {
    color: #FFFFFF;
    margin-bottom: 10px;
  }

  h2 {
    font-size: 24px;
    border-bottom: 2px solid #FFA500;
    padding-bottom: 10px;
  }

  h3 {
    font-size: 20px;
    border-bottom: 1px solid #FFA500;
    padding-bottom: 5px;
  }

  h4 {
    font-size: 18px;
  }

  /* 段落样式 */
  p {
    font-size: 16px;
    line-height: 1.6;
    color: #FFFFFF;
    margin-bottom: 15px;
  }

  /* 图片样式 */
  img {
    width: 100%;
    height: auto;
    border-radius: 10px;
    box-shadow: 0 4px 8px rgba(0,0,0,0.2);
    transition: transform 0.3s, box-shadow 0.3s;
  }

  img:hover {
    transform: scale(1.05);
    box-shadow: 0 8px 16px rgba(0,0,0,0.3);
  }

  /* 按钮样式 */
  .btn {
    background-color: #FFA500;
    color: #FFFFFF;
    padding: 10px 20px;
    border: none;
    border-radius: 5px;
    cursor: pointer;
    transition: background-color 0.3s ease;
    text-decoration: none;
    font-size: 16px;
  }

  .btn:hover {
    background-color: #FF8C00;
  }

  /* 代码块样式 */
  pre {
    background-color: rgba(0, 0, 0, 0.7);
    padding: 15px;
    border-radius: 8px;
    overflow-x: auto;
    font-size: 14px;
    line-height: 1.5;
    margin-bottom: 20px;
  }

  code {
    color: #00FF00;
    font-family: 'Courier New', Courier, monospace;
  }

  /* FAQ折叠模块样式 */
  .faq-item {
    border-bottom: 1px solid #ddd;
  }

  .faq-question {
    padding: 15px;
    background-color: rgba(255, 165, 0, 0.5);
    cursor: pointer;
    position: relative;
    transition: background-color 0.3s ease;
  }

  .faq-question:hover {
    background-color: rgba(255, 165, 0, 0.7);
  }

  .faq-answer {
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.5s ease;
    background-color: rgba(255, 255, 255, 0.1);
    padding: 0 15px;
  }

  .faq-item.active .faq-answer {
    max-height: 200px;
    padding: 15px;
  }

  /* 侧边导航样式 */
  .side-nav {
    position: fixed;
    left: -250px;
    top: 0;
    width: 250px;
    height: 100%;
    background-color: #0A2540;
    transition: left 0.3s ease;
    padding-top: 60px;
  }

  .side-nav.open {
    left: 0;
  }

  .toggle-button {
    position: fixed;
    left: 10px;
    top: 10px;
    background-color: #FFA500;
    border: none;
    padding: 10px;
    cursor: pointer;
    border-radius: 5px;
    transition: background-color 0.3s ease;
  }

  .toggle-button:hover {
    background-color: #FF8C00;
  }

  /* 回到顶部按钮样式 */
  .back-to-top {
    position: fixed;
    bottom: 30px;
    right: 30px;
    background-color: #32CD32;
    color: #FFFFFF;
    padding: 10px 15px;
    border: none;
    border-radius: 50%;
    cursor: pointer;
    display: none;
    transition: background-color 0.3s ease, transform 0.3s ease;
  }

  .back-to-top:hover {
    background-color: #228B22;
    transform: scale(1.1);
  }

  /* 响应式设计 */
  @media (max-width: 768px) {
    nav a {
      font-size: 16px;
    }
    .toggle-button {
      padding: 8px;
    }
    .container {
      grid-template-columns: 1fr;
      padding: 120px 10px 30px 10px;
    }
    h2 {
      font-size: 22px;
    }
    h3 {
      font-size: 18px;
    }
  }

  /* 章节导航系统样式 */
  .chapter-nav {
    position: fixed;
    top: 60px;
    right: 20px;
    background-color: rgba(10, 37, 64, 0.8);
    padding: 10px;
    border-radius: 5px;
    z-index: 1001;
  }

  .chapter-nav ul {
    list-style: none;
    padding: 0;
    margin: 0;
  }

  .chapter-nav li {
    margin-bottom: 10px;
  }

  .chapter-nav a {
    color: #FFFFFF;
    text-decoration: none;
    font-size: 14px;
    transition: color 0.3s ease;
  }

  .chapter-nav a:hover {
    color: #FFA500;
  }

  /* 代码示例专用样式 */
  .code-example {
    background-color: rgba(0, 0, 0, 0.8);
    padding: 20px;
    border-radius: 8px;
    margin-bottom: 30px;
    overflow-x: auto;
  }

  .code-example code {
    color: #00FF00;
    font-family: 'Courier New', Courier, monospace;
    font-size: 14px;
  }