:root {
    --primary-color: #00008B; /* 深蓝色 */
    --secondary-color: #8A2BE2; /* 紫色 */
    --accent-color: #00FF7F; /* 霓虹绿 */
    --background-color: #000000; /* 黑色 */
    --text-color: #FFFFFF; /* 白色 */
    --font-family: 'Roboto', sans-serif;
    --transition-speed: 0.3s;
  }

  * {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
  }

  body {
    background: linear-gradient(135deg, var(--background-color), #1a1a1a);
    color: var(--text-color);
    font-family: var(--font-family);
    line-height: 1.6;
    padding: 20px;
  }

  header {
    position: fixed;
    top: 0;
    width: 100%;
    background: rgba(0, 0, 0, 0.7);
    padding: 20px 40px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    transition: background var(--transition-speed) ease-in-out;
    z-index: 1000;
  }

  header.scrolled {
    background: rgba(0, 0, 0, 0.9);
  }

  header .logo {
    font-size: 1.5rem;
    font-weight: bold;
    color: var(--accent-color);
    text-decoration: none;
  }

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

  nav ul li a {
    color: var(--text-color);
    text-decoration: none;
    font-size: 1rem;
    transition: color var(--transition-speed);
  }

  nav ul li a:hover {
    color: var(--accent-color);
  }

  .hero {
    height: 100vh;
    display: flex;
    justify-content: center;
    align-items: center;
    position: relative;
    margin-top: 80px;
    background: url('https://images.gptkong.com/demo/sample1.png') no-repeat center center/cover;
  }

  .hero::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: linear-gradient(135deg, rgba(0, 0, 139, 0.7), rgba(138, 43, 226, 0.7));
    z-index: 1;
  }

  .hero-content {
    position: relative;
    z-index: 2;
    text-align: center;
    color: var(--text-color);
  }

  .hero-content h1 {
    font-size: 3rem;
    margin-bottom: 20px;
    animation: fadeIn 2s ease-in-out;
  }

  .hero-content p {
    font-size: 1.2rem;
    max-width: 600px;
    margin: 0 auto;
    animation: fadeIn 2s ease-in-out 0.5s;
  }

  @keyframes fadeIn {
    from { opacity: 0; transform: translateY(-20px); }
    to { opacity: 1; transform: translateY(0); }
  }

  .sections {
    display: grid;
    grid-template-columns: 1fr;
    gap: 40px;
    padding: 60px 20px;
  }

  .section {
    background: rgba(255, 255, 255, 0.1);
    padding: 20px;
    border-radius: 10px;
    position: relative;
    overflow: hidden;
  }

  .section h2, .section h3, .section h4 {
    color: var(--accent-color);
    margin-bottom: 15px;
  }

  .section p {
    color: var(--text-color);
    margin-bottom: 15px;
  }

  .section pre {
    background: rgba(0, 0, 0, 0.8);
    padding: 15px;
    border-radius: 5px;
    overflow-x: auto;
    color: #00FF7F;
    font-family: 'Courier New', Courier, monospace;
    margin-bottom: 15px;
  }

  .gallery {
    display: flex;
    flex-wrap: wrap;
    gap: 10px;
    justify-content: center;
  }

  .gallery img {
    width: 160px;
    height: 160px;
    object-fit: cover;
    border-radius: 5px;
    transition: transform var(--transition-speed);
  }

  .gallery img:hover {
    transform: scale(1.05);
  }

  .table-responsive {
    overflow-x: auto;
  }

  table {
    width: 100%;
    border-collapse: collapse;
    margin-top: 20px;
  }

  table th, table td {
    border: 1px solid var(--accent-color);
    padding: 10px;
    text-align: left;
  }

  table th {
    background: var(--secondary-color);
  }

  footer {
    text-align: center;
    padding: 20px;
    background: rgba(0, 0, 0, 0.9);
    color: var(--text-color);
    position: relative;
    margin-top: 40px;
  }

  .notice {
    font-size: 1rem;
    margin-top: 10px;
  }

  /* Responsive Styles */
  @media (min-width: 320px) {
    .hero-content h1 {
      font-size: 2rem;
    }

    .sections {
      padding: 40px 10px;
    }
  }

  @media (min-width: 480px) {
    .hero-content h1 {
      font-size: 2.5rem;
    }
  }

  @media (min-width: 768px) {
    .sections {
      grid-template-columns: 1fr 1fr;
    }

    .hero-content h1 {
      font-size: 3rem;
    }
  }

  @media (min-width: 1024px) {
    .sections {
      grid-template-columns: 1fr 1fr 1fr;
    }

    .gallery img {
      width: 200px;
      height: 200px;
    }
  }

  @media (min-width: 1200px) {
    .hero-content h1 {
      font-size: 3.5rem;
    }
  }

  @media (min-width: 1440px) {
    .sections {
      grid-template-columns: 1fr 1fr 1fr 1fr;
    }

    .gallery img {
      width: 220px;
      height: 220px;
    }
  }