:root {
    --primary-color: #0D47A1;
    --accent-color: #8E24AA;
    --electric-blue: #00B0FF;
    --fluorescent-green: #00E676;
    --background-color: #F5F5F5;
    --text-primary: #333333;
    --text-secondary: #666666;
    --card-bg: #FFFFFF;
    --section-spacing: 80px;
  }

  @font-face {
    font-family: 'Roboto';
    src: url('https://fonts.googleapis.com/css2?family=Roboto:wght@300;400;500;700&display=swap');
  }

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

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

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

  header {
    background: linear-gradient(135deg, var(--primary-color), var(--accent-color));
    padding: 20px 0;
    position: relative;
    z-index: 100;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.1);
  }

  .header-content {
    display: flex;
    justify-content: space-between;
    align-items: center;
  }

  .logo {
    font-size: 24px;
    font-weight: 700;
    color: white;
    text-decoration: none;
    display: flex;
    align-items: center;
  }

  .logo-icon {
    margin-right: 10px;
    width: 32px;
    height: 32px;
    background: var(--fluorescent-green);
    border-radius: 50%;
    display: inline-flex;
    align-items: center;
    justify-content: center;
  }

  .nav-links {
    display: flex;
    gap: 30px;
  }

  .nav-link {
    color: white;
    text-decoration: none;
    font-weight: 500;
    position: relative;
    transition: all 0.3s ease;
  }

  .nav-link:hover {
    color: var(--fluorescent-green);
  }

  .nav-link::after {
    content: '';
    position: absolute;
    bottom: -5px;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--fluorescent-green);
    transition: width 0.3s ease;
  }

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

  .hero {
    padding: 100px 0;
    background: linear-gradient(135deg, rgba(13, 71, 161, 0.8), rgba(142, 36, 170, 0.8)), url('https://images.gptkong.com/demo/sample1.png');
    background-size: cover;
    background-position: center;
    color: white;
    text-align: center;
    position: relative;
    overflow: hidden;
  }

  .hero::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: radial-gradient(circle, transparent 20%, rgba(0, 0, 0, 0.3) 100%);
  }

  .hero-content {
    position: relative;
    z-index: 1;
    max-width: 800px;
    margin: 0 auto;
  }

  .hero h1 {
    font-size: 48px;
    margin-bottom: 20px;
    animation: fadeInDown 1s ease-out;
  }

  .hero p {
    font-size: 20px;
    margin-bottom: 30px;
    animation: fadeInUp 1s ease-out 0.3s forwards;
    opacity: 0;
  }

  .notice {
    background: rgba(255, 255, 255, 0.2);
    backdrop-filter: blur(10px);
    padding: 15px;
    border-radius: 8px;
    margin: 40px auto;
    max-width: 600px;
    border: 1px solid rgba(255, 255, 255, 0.3);
  }

  .main-content {
    padding: var(--section-spacing) 0;
  }

  article {
    background: var(--card-bg);
    border-radius: 12px;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.05);
    padding: 40px;
    margin-bottom: var(--section-spacing);
  }

  article h2 {
    font-size: 32px;
    color: var(--primary-color);
    margin-bottom: 30px;
    position: relative;
    padding-bottom: 15px;
  }

  article h2::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 80px;
    height: 4px;
    background: linear-gradient(90deg, var(--primary-color), var(--accent-color));
    border-radius: 2px;
  }

  article h3 {
    font-size: 24px;
    color: var(--accent-color);
    margin: 30px 0 20px;
  }

  article p {
    font-size: 17px;
    line-height: 1.8;
    color: var(--text-primary);
    margin-bottom: 20px;
  }

  pre {
    background: #2d2d2d;
    border-radius: 8px;
    padding: 20px;
    margin: 25px 0;
    overflow-x: auto;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.1);
  }

  code {
    font-family: 'Courier New', monospace;
    color: #f8f8f2;
    font-size: 14px;
  }

  .code-container {
    position: relative;
  }

  .code-container::before {
    content: 'CSS';
    position: absolute;
    top: -10px;
    left: 20px;
    background: var(--accent-color);
    color: white;
    padding: 2px 10px;
    border-radius: 4px;
    font-size: 12px;
    font-weight: bold;
  }

  .image-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
    gap: 25px;
    margin: 40px 0;
  }

  .image-card {
    border-radius: 12px;
    overflow: hidden;
    box-shadow: 0 8px 20px rgba(0, 0, 0, 0.1);
    transition: transform 0.3s ease, box-shadow 0.3s ease;
    position: relative;
  }

  .image-card:hover {
    transform: translateY(-10px);
    box-shadow: 0 15px 30px rgba(0, 0, 0, 0.15);
  }

  .image-card img {
    width: 100%;
    height: 300px;
    object-fit: cover;
    display: block;
  }

  .image-card::after {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: linear-gradient(to top, rgba(0, 0, 0, 0.7), transparent 50%);
    opacity: 0;
    transition: opacity 0.3s ease;
  }

  .image-card:hover::after {
    opacity: 1;
  }

  footer {
    background: linear-gradient(135deg, var(--primary-color), var(--accent-color));
    color: white;
    padding: 40px 0;
    text-align: center;
  }

  .footer-content {
    max-width: 800px;
    margin: 0 auto;
  }

  .footer-links {
    display: flex;
    justify-content: center;
    gap: 30px;
    margin: 20px 0;
  }

  .footer-link {
    color: white;
    text-decoration: none;
    transition: color 0.3s ease;
  }

  .footer-link:hover {
    color: var(--fluorescent-green);
  }

  .copyright {
    margin-top: 20px;
    font-size: 14px;
    opacity: 0.8;
  }

  @keyframes fadeInDown {
    from {
      opacity: 0;
      transform: translateY(-30px);
    }
    to {
      opacity: 1;
      transform: translateY(0);
    }
  }

  @keyframes fadeInUp {
    from {
      opacity: 0;
      transform: translateY(30px);
    }
    to {
      opacity: 1;
      transform: translateY(0);
    }
  }

  @keyframes pulse {
    0% {
      transform: scale(1);
    }
    50% {
      transform: scale(1.05);
    }
    100% {
      transform: scale(1);
    }
  }

  @media (max-width: 768px) {
    .nav-links {
      display: none;
    }

    .hero h1 {
      font-size: 36px;
    }

    .hero p {
      font-size: 18px;
    }

    article {
      padding: 30px 20px;
    }

    article h2 {
      font-size: 28px;
    }

    article h3 {
      font-size: 22px;
    }

    .image-grid {
      grid-template-columns: 1fr;
    }
  }

  @media (max-width: 480px) {
    .hero {
      padding: 80px 0;
    }

    .hero h1 {
      font-size: 28px;
    }

    article h2 {
      font-size: 24px;
    }

    article h3 {
      font-size: 20px;
    }
  }