:root {
    --primary: #0D6EFD;
    --secondary: #F8FAFC;
    --accent: #FFA500;
    --text: #333333;
    --light: #FFFFFF;
    --shadow: 0 4px 20px rgba(0, 0, 0, 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: 'Roboto', sans-serif;
    color: var(--text);
    line-height: 1.6;
    background: var(--secondary);
    overflow-x: hidden;
  }

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

  /* Header Styles */
  header {
    background: linear-gradient(135deg, var(--primary) 0%, #6CAFF5 100%);
    color: var(--light);
    padding: 100px 0;
    text-align: center;
    position: relative;
    overflow: hidden;
    margin-bottom: 60px;
  }

  header::after {
    content: '';
    position: absolute;
    bottom: -50px;
    left: 0;
    width: 100%;
    height: 100px;
    background: var(--secondary);
    clip-path: polygon(0 0, 100% 50%, 100% 100%, 0% 100%);
  }

  header h1 {
    font-size: 2.8rem;
    margin-bottom: 20px;
    text-shadow: 0 2px 10px rgba(0, 0, 0, 0.2);
    animation: fadeIn 1s ease-out;
  }

  header p {
    font-size: 1.2rem;
    max-width: 700px;
    margin: 0 auto 30px;
    opacity: 0.9;
  }

  .reference-note {
    position: absolute;
    top: 20px;
    right: 20px;
    background: rgba(255, 255, 255, 0.2);
    padding: 8px 15px;
    border-radius: 20px;
    font-size: 0.9rem;
    backdrop-filter: blur(5px);
  }

  /* Navigation */
  .navbar {
    position: fixed;
    top: 0;
    width: 100%;
    background: rgba(13, 110, 253, 0.9);
    padding: 15px 0;
    z-index: 1000;
    backdrop-filter: blur(10px);
    box-shadow: var(--shadow);
    transition: var(--transition);
  }

  .navbar-container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
  }

  .nav-links {
    display: flex;
    gap: 25px;
  }

  .nav-links a {
    color: var(--light);
    text-decoration: none;
    font-weight: 500;
    position: relative;
    padding: 5px 0;
    transition: var(--transition);
  }

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

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

  /* Main Content */
  main {
    padding: 40px 0 100px;
  }

  article {
    background: var(--light);
    border-radius: 15px;
    padding: 40px;
    box-shadow: var(--shadow);
    margin-bottom: 60px;
  }

  article h2 {
    color: var(--primary);
    font-size: 2rem;
    margin-bottom: 25px;
    position: relative;
    padding-bottom: 15px;
  }

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

  article h3 {
    color: var(--primary);
    font-size: 1.5rem;
    margin: 30px 0 15px;
  }

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

  /* Code Blocks */
  pre {
    background: #2d2d2d;
    border-radius: 8px;
    padding: 20px;
    margin: 25px 0;
    overflow-x: auto;
    box-shadow: var(--shadow);
  }

  code {
    font-family: 'Courier New', monospace;
    color: #f8f8f2;
    font-size: 0.95rem;
  }

  .language-css, .language-html {
    display: block;
    white-space: pre;
  }

  /* Image Gallery */
  .image-gallery {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
    gap: 20px;
    margin: 40px 0;
  }

  .gallery-item {
    border-radius: 10px;
    overflow: hidden;
    box-shadow: var(--shadow);
    transition: var(--transition);
    position: relative;
  }

  .gallery-item:hover {
    transform: translateY(-5px);
    box-shadow: 0 10px 25px rgba(0, 0, 0, 0.15);
  }

  .gallery-item img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: var(--transition);
  }

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

  /* Tables */
  table {
    width: 100%;
    border-collapse: collapse;
    margin: 25px 0;
    box-shadow: var(--shadow);
    border-radius: 8px;
    overflow: hidden;
  }

  th, td {
    padding: 15px;
    text-align: left;
    border-bottom: 1px solid #e0e0e0;
  }

  th {
    background-color: var(--primary);
    color: var(--light);
    font-weight: 500;
  }

  tr:nth-child(even) {
    background-color: rgba(248, 250, 252, 0.5);
  }

  tr:hover {
    background-color: rgba(13, 110, 253, 0.05);
  }

  /* Back to Top Button */
  .back-to-top {
    position: fixed;
    bottom: 30px;
    right: 30px;
    width: 50px;
    height: 50px;
    background: var(--accent);
    color: var(--light);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    opacity: 0;
    visibility: hidden;
    transition: var(--transition);
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.2);
    z-index: 999;
  }

  .back-to-top.active {
    opacity: 1;
    visibility: visible;
  }

  .back-to-top:hover {
    background: #FF8C00;
    transform: translateY(-3px);
  }

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

  .fade-in {
    animation: fadeIn 0.8s ease-out forwards;
  }

  /* Responsive Design */
  @media (max-width: 768px) {
    header h1 {
      font-size: 2rem;
    }

    header p {
      font-size: 1rem;
    }

    .nav-links {
      gap: 15px;
    }

    article {
      padding: 25px;
    }

    article h2 {
      font-size: 1.6rem;
    }

    article h3 {
      font-size: 1.3rem;
    }
  }

  @media (max-width: 480px) {
    .navbar-container {
      flex-direction: column;
      gap: 15px;
    }

    .nav-links {
      flex-wrap: wrap;
      justify-content: center;
    }

    header {
      padding: 80px 0;
    }

    header h1 {
      font-size: 1.8rem;
    }

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