:root {
    --primary-color: #C7E9C0;
    --secondary-color: #38761D;
    --accent-color: #A66D4F;
    --highlight-color: #4A90E2;
    --dark-color: #1A3C1A;
    --light-color: #F8F9FA;
    --text-color: #333;
    --border-radius: 12px;
    --box-shadow: 0 8px 24px rgba(0, 0, 0, 0.1);
    --transition: all 0.3s cubic-bezier(0.25, 0.8, 0.25, 1);
  }

  @font-face {
    font-family: 'Roboto';
    src: local('Roboto'), url(https://fonts.gstatic.com/s/roboto/v30/KFOmCnqEu92Fr1Mu4mxK.woff2) format('woff2');
    font-display: swap;
  }

  @font-face {
    font-family: 'Open Sans';
    src: local('Open Sans'), url(https://fonts.gstatic.com/s/opensans/v23/mem8YaGs126MiZpBA-UFVZ0e.woff2) format('woff2');
    font-display: swap;
  }

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

  body {
    font-family: 'Open Sans', sans-serif;
    line-height: 1.6;
    color: var(--text-color);
    background: linear-gradient(135deg, #F8F9FA 0%, #E9F5E9 100%);
    background-attachment: fixed;
    overflow-x: hidden;
  }

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

  /* Header Styles */
  header {
    background: linear-gradient(135deg, var(--primary-color) 0%, var(--secondary-color) 100%);
    padding: 2rem 0;
    box-shadow: var(--box-shadow);
    position: relative;
    overflow: hidden;
  }

  header::before {
    content: "";
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: url('https://images.gptkong.com/demo/sample3.png') no-repeat;
    background-size: cover;
    opacity: 0.1;
    z-index: 0;
  }

  .header-content {
    position: relative;
    z-index: 1;
    display: flex;
    flex-direction: column;
    align-items: center;
    text-align: center;
    color: white;
  }

  .header-title {
    font-family: 'Roboto', sans-serif;
    font-size: 2.5rem;
    margin-bottom: 1rem;
    text-shadow: 0 2px 4px rgba(0, 0, 0, 0.2);
  }

  .header-subtitle {
    font-size: 1.2rem;
    max-width: 800px;
    margin-bottom: 2rem;
  }

  .design-reference {
    background-color: rgba(255, 255, 255, 0.2);
    padding: 0.5rem 1rem;
    border-radius: 50px;
    font-size: 0.9rem;
    backdrop-filter: blur(5px);
  }

  /* Navigation */
  nav {
    background-color: var(--secondary-color);
    position: sticky;
    top: 0;
    z-index: 100;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.1);
  }

  .nav-container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1rem 2rem;
  }

  .logo {
    font-family: 'Roboto', sans-serif;
    font-size: 1.5rem;
    color: white;
    text-decoration: none;
    font-weight: bold;
  }

  .nav-links {
    display: flex;
    list-style: none;
  }

  .nav-links li {
    margin-left: 2rem;
  }

  .nav-links a {
    color: white;
    text-decoration: none;
    font-weight: 500;
    position: relative;
    padding: 0.5rem 0;
    transition: var(--transition);
  }

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

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

  /* Main Content */
  main {
    padding: 3rem 0;
  }

  article {
    background-color: white;
    border-radius: var(--border-radius);
    box-shadow: var(--box-shadow);
    padding: 3rem;
    margin-bottom: 3rem;
  }

  article h2 {
    font-family: 'Roboto', sans-serif;
    color: var(--secondary-color);
    font-size: 2rem;
    margin-bottom: 1.5rem;
    position: relative;
    padding-bottom: 0.5rem;
  }

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

  article h3 {
    font-family: 'Roboto', sans-serif;
    color: var(--dark-color);
    font-size: 1.5rem;
    margin: 2rem 0 1rem;
  }

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

  /* Code Blocks */
  pre {
    background: linear-gradient(135deg, #2D3748 0%, #1A202C 100%);
    border-radius: var(--border-radius);
    padding: 1.5rem;
    margin: 2rem 0;
    overflow: auto;
    box-shadow: var(--box-shadow);
  }

  code {
    font-family: 'Roboto Mono', monospace;
    color: #E2E8F0;
    font-size: 0.9rem;
  }

  .language-css {
    color: #81E6D9;
  }

  /* Tables */
  table {
    width: 100%;
    border-collapse: collapse;
    margin: 2rem 0;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
    border-radius: var(--border-radius);
    overflow: hidden;
  }

  th, td {
    padding: 1rem;
    text-align: left;
    border-bottom: 1px solid rgba(0, 0, 0, 0.1);
  }

  th {
    background-color: var(--secondary-color);
    color: white;
    font-family: 'Roboto', sans-serif;
  }

  tr:nth-child(even) {
    background-color: rgba(199, 233, 192, 0.2);
  }

  tr:hover {
    background-color: rgba(74, 144, 226, 0.1);
  }

  /* Image Gallery */
  .image-gallery {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
    gap: 1.5rem;
    margin: 3rem 0;
  }

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

  .gallery-item:hover {
    transform: translateY(-10px);
    box-shadow: 0 12px 28px rgba(0, 0, 0, 0.15);
  }

  .gallery-item img {
    width: 100%;
    height: 300px;
    object-fit: cover;
    transition: var(--transition);
  }

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

  /* Cards */
  .card-container {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(350px, 1fr));
    gap: 2rem;
    margin: 3rem 0;
  }

  .card {
    background: white;
    border-radius: var(--border-radius);
    box-shadow: var(--box-shadow);
    overflow: hidden;
    transition: var(--transition);
  }

  .card:hover {
    transform: translateY(-10px);
    box-shadow: 0 12px 28px rgba(0, 0, 0, 0.15);
  }

  .card-image {
    height: 200px;
    overflow: hidden;
  }

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

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

  .card-content {
    padding: 1.5rem;
  }

  .card-title {
    font-family: 'Roboto', sans-serif;
    color: var(--secondary-color);
    margin-bottom: 0.5rem;
  }

  /* Footer */
  footer {
    background: linear-gradient(135deg, var(--secondary-color) 0%, var(--dark-color) 100%);
    color: white;
    padding: 3rem 0;
    text-align: center;
  }

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

  .footer-links {
    display: flex;
    justify-content: center;
    list-style: none;
    margin: 1.5rem 0;
  }

  .footer-links li {
    margin: 0 1rem;
  }

  .footer-links a {
    color: white;
    text-decoration: none;
    transition: var(--transition);
  }

  .footer-links a:hover {
    color: var(--highlight-color);
  }

  .copyright {
    opacity: 0.8;
    font-size: 0.9rem;
  }

  /* Responsive Design */
  @media (max-width: 768px) {
    .nav-container {
      flex-direction: column;
      padding: 1rem;
    }

    .nav-links {
      margin-top: 1rem;
    }

    .nav-links li {
      margin-left: 1rem;
    }

    article {
      padding: 2rem;
    }

    .header-title {
      font-size: 2rem;
    }

    .card-container {
      grid-template-columns: 1fr;
    }
  }

  @media (max-width: 480px) {
    .nav-links {
      flex-direction: column;
      align-items: center;
    }

    .nav-links li {
      margin: 0.5rem 0;
    }

    article {
      padding: 1.5rem;
    }

    .header-title {
      font-size: 1.8rem;
    }
  }

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

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

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

  /* Utility Classes */
  .text-center { text-align: center; }
  .mt-1 { margin-top: 1rem; }
  .mt-2 { margin-top: 2rem; }
  .mt-3 { margin-top: 3rem; }
  .mb-1 { margin-bottom: 1rem; }
  .mb-2 { margin-bottom: 2rem; }
  .mb-3 { margin-bottom: 3rem; }
  .py-1 { padding-top: 1rem; padding-bottom: 1rem; }
  .py-2 { padding-top: 2rem; padding-bottom: 2rem; }
  .py-3 { padding-top: 3rem; padding-bottom: 3rem; }