:root {
    --primary: #4B0082;
    --secondary: #00008B;
    --accent: #FFD700;
    --text: #FFFFFF;
    --bg-dark: #121212;
    --bg-light: #1E1E1E;
    --highlight: #6A0DAD;
  }

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

  body {
    font-family: 'Roboto', sans-serif;
    line-height: 1.6;
    color: var(--text);
    background: var(--bg-dark);
    overflow-x: hidden;
  }

  .container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
  }

  header {
    background: linear-gradient(135deg, var(--primary), var(--secondary));
    padding: 2rem 0;
    text-align: center;
    position: relative;
    overflow: hidden;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.5);
  }

  header::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: url('https://images.gptkong.com/demo/sample1.png') center/cover no-repeat;
    opacity: 0.1;
    z-index: 0;
  }

  h1, h2, h3, h4 {
    font-family: 'Helvetica', sans-serif;
    margin-bottom: 1.5rem;
    position: relative;
  }

  h1 {
    font-size: 2.5rem;
    background: linear-gradient(90deg, var(--accent), var(--text));
    -webkit-background-clip: text;
    background-clip: text;
    color: transparent;
    text-shadow: 0 2px 10px rgba(0, 0, 0, 0.3);
  }

  h2 {
    font-size: 2rem;
    color: var(--accent);
    padding-bottom: 0.5rem;
    border-bottom: 2px solid var(--highlight);
  }

  h3 {
    font-size: 1.5rem;
    color: var(--text);
    margin-top: 2rem;
  }

  p {
    margin-bottom: 1.5rem;
    font-size: 1.1rem;
  }

  .grid-container {
    display: grid;
    grid-template-columns: 1fr;
    gap: 2rem;
    padding: 2rem 0;
  }

  .card {
    background: var(--bg-light);
    border-radius: 15px;
    padding: 2rem;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.3);
    transition: transform 0.3s ease, box-shadow 0.3s ease;
    position: relative;
    overflow: hidden;
  }

  .card:hover {
    transform: translateY(-10px);
    box-shadow: 0 15px 40px rgba(0, 0, 0, 0.4);
  }

  .card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 5px;
    background: linear-gradient(90deg, var(--primary), var(--accent));
  }

  .image-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 1.5rem;
    margin: 2rem 0;
  }

  .image-card {
    border-radius: 10px;
    overflow: hidden;
    box-shadow: 0 5px 15px rgba(0, 0, 0, 0.2);
    transition: transform 0.3s ease;
  }

  .image-card:hover {
    transform: scale(1.03);
  }

  .image-card img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: transform 0.5s ease;
  }

  .image-card:hover img {
    transform: scale(1.1);
  }

  pre {
    background: #1a1a1a;
    border-radius: 10px;
    padding: 1.5rem;
    margin: 1.5rem 0;
    overflow: auto;
    box-shadow: inset 0 0 10px rgba(0, 0, 0, 0.5);
    border-left: 5px solid var(--accent);
  }

  code {
    font-family: 'Courier New', monospace;
    color: #f8f8f2;
  }

  .note {
    background: rgba(255, 215, 0, 0.1);
    border-left: 5px solid var(--accent);
    padding: 1rem;
    margin: 1.5rem 0;
    border-radius: 0 5px 5px 0;
  }

  .note::before {
    content: '提示';
    display: block;
    font-weight: bold;
    color: var(--accent);
    margin-bottom: 0.5rem;
  }

  .parallax-section {
    height: 400px;
    background-attachment: fixed;
    background-position: center;
    background-repeat: no-repeat;
    background-size: cover;
    position: relative;
    margin: 3rem 0;
    display: flex;
    align-items: center;
    justify-content: center;
    text-align: center;
  }

  .parallax-section::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.6);
  }

  .parallax-content {
    position: relative;
    z-index: 1;
    max-width: 800px;
    padding: 2rem;
  }

  .button {
    display: inline-block;
    background: linear-gradient(90deg, var(--primary), var(--highlight));
    color: var(--text);
    padding: 0.8rem 1.5rem;
    border-radius: 50px;
    text-decoration: none;
    font-weight: bold;
    margin: 1rem 0;
    box-shadow: 0 5px 15px rgba(0, 0, 0, 0.3);
    transition: transform 0.3s ease, box-shadow 0.3s ease;
  }

  .button:hover {
    transform: translateY(-3px);
    box-shadow: 0 8px 20px rgba(0, 0, 0, 0.4);
  }

  footer {
    background: linear-gradient(135deg, var(--primary), var(--secondary));
    padding: 2rem 0;
    text-align: center;
    margin-top: 3rem;
  }

  @media (max-width: 768px) {
    h1 {
      font-size: 2rem;
    }
    
    h2 {
      font-size: 1.5rem;
    }
    
    .grid-container {
      grid-template-columns: 1fr;
    }
    
    .image-grid {
      grid-template-columns: 1fr;
    }
  }

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

  .fade-in {
    animation: fadeIn 1s ease-out forwards;
  }

  .delay-1 { animation-delay: 0.2s; }
  .delay-2 { animation-delay: 0.4s; }
  .delay-3 { animation-delay: 0.6s; }

  .nav-links {
    display: flex;
    justify-content: center;
    gap: 2rem;
    margin: 2rem 0;
    flex-wrap: wrap;
  }

  .nav-link {
    color: var(--accent);
    text-decoration: none;
    font-weight: bold;
    position: relative;
    padding: 0.5rem 0;
  }

  .nav-link::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--accent);
    transition: width 0.3s ease;
  }

  .nav-link:hover::after {
    width: 100%;
  }

  .reference {
    background: rgba(255, 255, 255, 0.05);
    padding: 1rem;
    border-radius: 10px;
    margin: 2rem 0;
    text-align: center;
    font-style: italic;
  }