:root {
    --primary-dark: #1A237E;
    --primary-light: #6A1B9A;
    --accent-green: #388E3C;
    --accent-orange: #FFA000;
    --text-light: #ffffff;
    --text-dark: #333333;
    --bg-gradient: linear-gradient(135deg, var(--primary-dark), var(--primary-light));
    --card-bg: rgba(255, 255, 255, 0.1);
    --transition: all 0.3s cubic-bezier(0.25, 0.8, 0.25, 1);
  }

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

  body {
    font-family: 'Montserrat', 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    line-height: 1.6;
    color: var(--text-light);
    background: var(--bg-gradient);
    min-height: 100%;
    overflow-x: hidden;
  }

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

  .header {
    text-align: center;
    padding: 40px 0;
    position: relative;
  }

  .header::after {
    content: "";
    display: block;
    width: 100px;
    height: 4px;
    background: var(--accent-orange);
    margin: 20px auto;
    border-radius: 2px;
  }

  .header h1 {
    font-size: 2.5rem;
    margin-bottom: 15px;
    text-shadow: 0 2px 4px rgba(0, 0, 0, 0.3);
  }

  .header p {
    font-size: 1.1rem;
    opacity: 0.9;
  }

  .reference-banner {
    background-color: rgba(0, 0, 0, 0.3);
    padding: 10px;
    text-align: center;
    font-size: 0.9rem;
    margin-bottom: 30px;
    border-radius: 4px;
  }

  .article-container {
    background-color: rgba(0, 0, 0, 0.2);
    border-radius: 10px;
    padding: 30px;
    margin-bottom: 40px;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.2);
  }

  article h2 {
    font-size: 1.8rem;
    margin: 30px 0 20px;
    color: var(--text-light);
    position: relative;
    padding-bottom: 10px;
  }

  article h2::after {
    content: "";
    position: absolute;
    bottom: 0;
    left: 0;
    width: 60px;
    height: 3px;
    background: var(--accent-green);
    border-radius: 3px;
  }

  article h3 {
    font-size: 1.5rem;
    margin: 25px 0 15px;
    color: var(--text-light);
  }

  article p {
    margin-bottom: 20px;
    font-size: 1.1rem;
    line-height: 1.7;
  }

  .image-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 20px;
    margin: 30px 0;
  }

  .image-card {
    background: var(--card-bg);
    border-radius: 8px;
    overflow: hidden;
    transition: var(--transition);
    box-shadow: 0 5px 15px rgba(0, 0, 0, 0.1);
  }

  .image-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 15px 30px rgba(0, 0, 0, 0.2);
  }

  .image-card img {
    width: 100%;
    height: auto;
    display: block;
    border-radius: 8px 8px 0 0;
  }

  .image-caption {
    padding: 15px;
    text-align: center;
    font-size: 0.9rem;
  }

  pre {
    background: rgba(0, 0, 0, 0.3);
    border-radius: 8px;
    padding: 20px;
    margin: 20px 0;
    overflow: auto;
    font-family: 'Courier New', Courier, monospace;
    position: relative;
  }

  pre::before {
    content: "CSS";
    position: absolute;
    top: 5px;
    left: 10px;
    font-size: 0.8rem;
    color: var(--accent-orange);
  }

  code {
    font-family: 'Courier New', Courier, monospace;
    color: var(--accent-green);
  }

  table {
    width: 100%;
    border-collapse: collapse;
    margin: 25px 0;
    background: var(--card-bg);
    border-radius: 8px;
    overflow: hidden;
  }

  th, td {
    padding: 12px 15px;
    text-align: left;
    border-bottom: 1px solid rgba(255, 255, 255, 0.1);
  }

  th {
    background-color: rgba(0, 0, 0, 0.2);
    font-weight: 600;
  }

  tr:hover {
    background-color: rgba(255, 255, 255, 0.05);
  }

  .nav-links {
    display: flex;
    justify-content: center;
    margin: 30px 0;
    flex-wrap: wrap;
  }

  .nav-link {
    margin: 0 10px;
    padding: 8px 15px;
    background: var(--card-bg);
    border-radius: 20px;
    color: var(--text-light);
    text-decoration: none;
    transition: var(--transition);
    font-size: 0.9rem;
  }

  .nav-link:hover {
    background: var(--accent-orange);
    transform: translateY(-2px);
  }

  .footer {
    text-align: center;
    padding: 30px 0;
    margin-top: 50px;
    border-top: 1px solid rgba(255, 255, 255, 0.1);
  }

  @media (max-width: 768px) {
    .header h1 {
      font-size: 2rem;
    }
    
    .article-container {
      padding: 20px;
    }
    
    article h2 {
      font-size: 1.6rem;
    }
    
    article h3 {
      font-size: 1.3rem;
    }
  }

  @media (max-width: 480px) {
    .header h1 {
      font-size: 1.8rem;
    }
    
    .image-grid {
      grid-template-columns: 1fr;
    }
    
    .nav-links {
      flex-direction: column;
      align-items: center;
    }
    
    .nav-link {
      margin: 5px 0;
    }
  }