/* 全局样式设置 */
  body {
    margin: 0;
    padding: 0;
    background: linear-gradient(135deg, #0f2027, #203a43, #2c5364); /* 渐变背景 */
    color: #ffffff;
    font-family: 'Roboto', sans-serif; /* 使用现代无衬线字体 */
    line-height: 1.6;
    font-size: 16px; /* 正文字号 */
    overflow-x: hidden; /* 避免左右出现滚动条 */
  }

  /* 导航栏样式 */
  .nav-bar {
    position: fixed;
    top: 0;
    width: 100%;
    background: rgba(32, 58, 67, 0.8); /* 半透明背景 */
    display: flex;
    justify-content: space-around;
    padding: 15px 0;
    z-index: 1000;
    transition: background 0.3s ease;
  }

  .nav-bar a {
    color: #ffffff;
    text-decoration: none;
    font-size: 16px;
    transition: color 0.3s ease;
  }

  .nav-bar a:hover {
    color: #6a5acd; /* 点缀色变化 */
  }

  /* 章节点间分隔样式 */
  .section {
    padding: 100px 50px 50px 50px;
    background: rgba(255, 255, 255, 0.05);
    margin: 20px 0;
    border-radius: 10px;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1); /* 阴影效果 */
  }

  /* 标题样式 */
  h2, h3, h4 {
    font-family: 'Roboto', sans-serif;
    color: #ffffff;
    margin-bottom: 20px;
  }

  h2 {
    font-size: 28px;
    color: #6a5acd;
    position: relative;
  }

  h2::after {
    content: '';
    display: block;
    width: 50px;
    height: 3px;
    background: #836fff;
    margin-top: 10px;
    transition: width 0.3s ease;
  }

  h2:hover::after {
    width: 100px;
  }

  h3 {
    font-size: 22px;
    color: #836fff;
  }

  /* 段落样式 */
  p {
    font-size: 16px;
    line-height: 1.6;
    color: #ffffff;
    transition: color 0.3s ease;
  }

  p:hover {
    color: #dcdcdc;
  }

  /* 图片装饰样式 */
  .decorative-image {
    width: 320px;
    height: 320px;
    border-radius: 15px; /* 圆角 */
    box-shadow: 0 4px 8px rgba(0, 0, 0, 0.2); /* 阴影 */
    margin: 20px;
    transition: transform 0.3s ease, box-shadow 0.3s ease;
    cursor: pointer;
  }

  .decorative-image:hover {
    transform: scale(1.05); /* 悬浮放大效果 */
    box-shadow: 0 8px 16px rgba(0, 0, 0, 0.3); /* 阴影加深 */
  }

  /* 代码块样式 */
  pre {
    background: rgba(0, 0, 0, 0.7);
    padding: 20px;
    border-radius: 10px;
    overflow-x: auto;
    margin: 20px 0;
  }

  code {
    color: #00ff00;
    font-family: 'Courier New', Courier, monospace;
    font-size: 14px;
  }

  /* 卡片式设计样式 */
  .card-container {
    display: flex;
    flex-wrap: wrap;
    justify-content: space-around;
    padding: 50px;
  }

  .card {
    background: rgba(255, 255, 255, 0.1);
    border: 1px solid rgba(255, 255, 255, 0.2);
    border-radius: 10px;
    width: 300px;
    margin: 20px;
    padding: 20px;
    transition: transform 0.3s ease, background 0.3s ease;
    cursor: pointer;
  }

  .card:hover {
    transform: scale(1.05);
    background: rgba(255, 255, 255, 0.2);
  }

  .card-header {
    font-size: 20px;
    margin-bottom: 10px;
    color: #6a5acd;
  }

  .card-content {
    font-size: 14px;
    color: #ffffff;
  }

  /* 侧边栏样式 */
  .sidebar {
    position: fixed;
    left: 0;
    top: 60px;
    width: 200px;
    height: calc(100% - 60px);
    background: rgba(32, 58, 67, 0.9);
    padding: 20px;
    box-sizing: border-box;
    transition: width 0.3s ease;
  }

  .sidebar.collapsed {
    width: 60px;
  }

  .sidebar a {
    display: block;
    color: #ffffff;
    text-decoration: none;
    margin: 15px 0;
    font-size: 14px;
    transition: color 0.3s ease;
  }

  .sidebar a:hover {
    color: #6a5acd;
  }

  /* 互动模块样式 */
  .community-section {
    background: rgba(32, 58, 67, 0.8);
    padding: 30px 50px;
    display: flex;
    justify-content: space-around;
    align-items: center;
    flex-wrap: wrap;
    transition: background 0.3s ease;
  }

  .community-box {
    background: rgba(255, 255, 255, 0.1);
    border: 1px solid rgba(255, 255, 255, 0.2);
    border-radius: 10px;
    width: 300px;
    padding: 20px;
    margin: 15px;
    transition: transform 0.3s ease, background 0.3s ease;
    cursor: pointer;
  }

  .community-box:hover {
    transform: translateY(-10px);
    background: rgba(255, 255, 255, 0.2);
  }

  /* 响应式设计 */
  @media (max-width: 768px) {
    .nav-bar {
      flex-direction: column;
    }

    .sidebar {
      display: none;
    }

    .card-container {
      flex-direction: column;
      align-items: center;
    }
  }

  /* 高级CSS3动画效果 */
  .particle-animation {
    position: absolute;
    width: 100%;
    height: 100%;
    background: transparent;
    animation: moveParticles 10s linear infinite;
  }

  @keyframes moveParticles {
    0% { background-position: 0 0; }
    100% { background-position: 1000px 1000px; }
  }

  /* 导航栏滚动效果 */
  .nav-bar.scrolled {
    background: rgba(32, 58, 67, 1);
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
  }

  /* 交互式图表样式 */
  .chart-container {
    width: 100%;
    height: 400px;
    background: rgba(255, 255, 255, 0.1);
    border-radius: 10px;
    padding: 20px;
    box-sizing: border-box;
    position: relative;
  }

  .chart-bar {
    position: absolute;
    bottom: 0;
    width: 40px;
    background: #6a5acd;
    transition: height 0.3s ease, background 0.3s ease;
  }

  .chart-bar:hover {
    background: #836fff;
  }

  /* 字体与动效结合的样式 */
  h2, h3 {
    transition: all 0.3s ease;
  }

  p {
    transition: color 0.3s ease;
  }

  p:hover {
    color: #dcdcdc;
  }

  /* 清晰的章节导航系统样式 */
  .chapter-nav {
    position: fixed;
    right: 20px;
    top: 100px;
    display: flex;
    flex-direction: column;
  }

  .chapter-nav a {
    color: #ffffff;
    text-decoration: none;
    margin: 10px 0;
    padding: 10px;
    background: rgba(106, 90, 205, 0.7);
    border-radius: 5px;
    transition: background 0.3s ease;
  }

  .chapter-nav a:hover {
    background: #836fff;
  }