/* 
    全局样式设置
    设置页面的基础字体、背景渐变、颜色搭配等，确保整体色彩和谐。
  */
  body {
    margin: 0;
    padding: 0;
    font-family: 'Roboto', sans-serif;
    background: linear-gradient(135deg, #0d47a1, #6a1b9a);
    background-size: 400% 400%;
    animation: gradientAnimation 15s ease infinite;
    color: #ffffff;
    line-height: 1.6;
  }

  @keyframes gradientAnimation {
    0% { background-position: 0% 50%; }
    50% { background-position: 100% 50%; }
    100% { background-position: 0% 50%; }
  }

  /* 
    渐变极光效果，创建动态背景层
  */
  .aurora {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    pointer-events: none;
    overflow: hidden;
    z-index: -1;
  }

  .aurora::before, .aurora::after {
    content: '';
    position: absolute;
    top: -50%;
    left: -50%;
    width: 200%;
    height: 200%;
    background: radial-gradient(circle, rgba(255,255,255,0.2) 0%, rgba(0,0,0,0) 70%);
    animation: auroraFlow 20s linear infinite;
    mix-blend-mode: screen;
  }

  .aurora::after {
    animation-delay: -10s;
    background: radial-gradient(circle, rgba(0,255,0,0.2) 0%, rgba(0,0,0,0) 70%);
  }

  @keyframes auroraFlow {
    0% { transform: rotate(0deg); }
    100% { transform: rotate(360deg); }
  }

  /* 
    导航栏样式设置
    包含固定在顶部的导航栏，响应式设计，悬停效果
  */
  header {
    position: fixed;
    top: 0;
    width: 100%;
    background: rgba(0, 0, 0, 0.5);
    padding: 15px 30px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    z-index: 1000;
    box-shadow: 0 2px 4px rgba(0,0,0,0.3);
  }

  nav ul {
    list-style: none;
    display: flex;
    gap: 20px;
    margin: 0;
    padding: 0;
  }

  nav ul li {
    position: relative;
  }

  nav ul li a {
    color: #ffffff;
    text-decoration: none;
    font-weight: 500;
    transition: color 0.3s;
  }

  nav ul li a:hover {
    color: #ffeb3b;
  }

  nav ul li ul {
    display: none;
    position: absolute;
    top: 35px;
    left: 0;
    background: rgba(0, 0, 0, 0.7);
    padding: 10px;
    border-radius: 5px;
  }

  nav ul li:hover ul {
    display: block;
  }

  nav ul li ul li {
    margin: 5px 0;
  }

  /* 
    菜单切换按钮用于移动端导航
  */
  .menu-toggle {
    display: none;
    cursor: pointer;
    color: #ffffff;
    font-size: 24px;
  }

  @media (max-width: 768px) {
    nav ul {
      flex-direction: column;
      background: rgba(0, 0, 0, 0.9);
      position: absolute;
      top: 60px;
      left: 0;
      width: 100%;
      display: none;
    }

    nav ul.active {
      display: flex;
    }

    .menu-toggle {
      display: block;
    }
  }

  /* 
    主要内容区域样式
    包括模块划分、对齐方式、背景色等
  */
  .module {
    padding: 80px 20px;
    display: flex;
    flex-direction: column;
    align-items: center;
    text-align: center;
  }

  .module:nth-child(even) {
    background: rgba(255, 255, 255, 0.05);
  }

  .module h2, .module h3, .module h4 {
    font-size: 2em;
    margin-bottom: 20px;
    color: #ffffff;
    text-shadow: 2px 2px 4px rgba(0,0,0,0.6);
  }

  .module p {
    max-width: 800px;
    line-height: 1.8;
    font-size: 1.1em;
    color: #eeeeee;
  }

  /* 
    按钮样式设置
    包括颜色、圆角、动画效果
  */
  .btn {
    background: #ffeb3b;
    color: #000000;
    padding: 12px 25px;
    border: none;
    border-radius: 25px;
    font-size: 16px;
    cursor: pointer;
    transition: transform 0.3s, background 0.3s;
    margin-top: 20px;
  }

  .btn:hover {
    transform: scale(1.05);
    background: #fdd835;
  }

  /* 
    图片样式设置
    包括圆角、阴影、悬停效果
  */
  img.decorative {
    width: 320px;
    height: 320px;
    border-radius: 15px;
    box-shadow: 0 4px 8px rgba(0,0,0,0.3);
    transition: transform 0.3s, box-shadow 0.3s;
    margin: 20px;
  }

  img.decorative:hover {
    transform: scale(1.05);
    box-shadow: 0 8px 16px rgba(0,0,0,0.4);
  }

  /* 
    代码块样式设置
    区分于正文内容，增加可读性
  */
  pre code {
    background: rgba(0, 0, 0, 0.7);
    padding: 15px;
    border-radius: 10px;
    display: block;
    overflow-x: auto;
    color: #ffeb3b;
    font-family: 'Courier New', Courier, monospace;
    margin: 20px 0;
  }

  /* 
    折叠区域样式设置
    用于次要信息的隐藏与展开
  */
  details {
    width: 80%;
    max-width: 800px;
    margin: 20px auto;
    background: rgba(255, 235, 59, 0.1);
    padding: 15px;
    border-radius: 10px;
    cursor: pointer;
    transition: background 0.3s;
  }

  details:hover {
    background: rgba(255, 235, 59, 0.2);
  }

  details summary {
    font-size: 1.2em;
    font-weight: bold;
    color: #ffeb3b;
  }

  /* 
    导航链接样式增强
  */
  .navigation {
    position: fixed;
    top: 80px;
    right: 20px;
    background: rgba(0,0,0,0.6);
    padding: 10px 15px;
    border-radius: 10px;
    z-index: 999;
  }

  .navigation a {
    display: block;
    color: #ffffff;
    text-decoration: none;
    margin: 10px 0;
    transition: color 0.3s;
  }

  .navigation a:hover {
    color: #ffeb3b;
  }

  /* 
    提示信息样式设置
    显著位置展示提示文字
  */
  .highlight {
    background: rgba(255, 235, 59, 0.3);
    padding: 10px 20px;
    border-radius: 5px;
    font-size: 1.2em;
    margin: 40px 0;
    box-shadow: 0 2px 4px rgba(0,0,0,0.3);
  }

  /* 
    表格样式设置
    优化数据展示的视觉效果
  */
  table {
    width: 90%;
    border-collapse: collapse;
    margin: 20px auto;
    background: rgba(255, 255, 255, 0.1);
    border-radius: 10px;
    overflow: hidden;
  }

  thead {
    background: rgba(0, 0, 0, 0.3);
  }

  th, td {
    padding: 15px;
    text-align: left;
    border-bottom: 1px solid rgba(255, 255, 255, 0.2);
  }

  tbody tr:hover {
    background: rgba(255, 235, 59, 0.2);
  }

  /* 
    响应式设计媒体查询
    针对不同屏幕尺寸调整布局
  */
  @media (max-width: 768px) {
    .module {
      padding: 60px 15px;
    }

    img.decorative {
      width: 100%;
      height: auto;
    }

    .navigation {
      top: auto;
      bottom: 20px;
      right: 10px;
    }
  }