:root {
    --primary-color: #56ab2f;
    --secondary-color: #6a11cb;
    --accent-color: #a8e063;
    --dark-bg: #1a1a2e;
    --light-bg: #f8f9fa;
    --text-color: #333;
    --light-text: #f8f9fa;
    --border-radius: 12px;
    --box-shadow: 0 10px 30px rgba(0,0,0,0.1);
    --transition: all 0.3s ease;
  }

  * {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: 'Montserrat', 'Open Sans', sans-serif;
  }

  body {
    background-color: var(--light-bg);
    color: var(--text-color);
    line-height: 1.6;
    overflow-x: hidden;
  }

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

  /* Header Styles */
  header {
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    color: white;
    padding: 2rem 0;
    position: relative;
    overflow: hidden;
    margin-bottom: 3rem;
  }

  header::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: url('https://images.gptkong.com/demo/sample1.png') no-repeat center right;
    background-size: contain;
    opacity: 0.2;
  }

  .header-content {
    position: relative;
    z-index: 2;
    text-align: center;
    padding: 2rem;
  }

  .header-content h1 {
    font-size: 2.5rem;
    margin-bottom: 1rem;
    text-shadow: 0 2px 4px rgba(0,0,0,0.2);
  }

  .header-content p {
    font-size: 1.2rem;
    max-width: 800px;
    margin: 0 auto;
  }

  /* Navigation */
  nav {
    position: sticky;
    top: 0;
    background: rgba(255,255,255,0.95);
    backdrop-filter: blur(10px);
    box-shadow: 0 2px 15px rgba(0,0,0,0.1);
    z-index: 100;
    transition: var(--transition);
  }

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

  .nav-links {
    display: flex;
    gap: 2rem;
  }

  .nav-links a {
    color: var(--text-color);
    text-decoration: none;
    font-weight: 600;
    transition: var(--transition);
    position: relative;
  }

  .nav-links a:hover {
    color: var(--primary-color);
  }

  .nav-links a::after {
    content: '';
    position: absolute;
    bottom: -5px;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--primary-color);
    transition: var(--transition);
  }

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

  /* Main Content */
  main {
    padding: 2rem 0;
  }

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

  article h2 {
    color: var(--primary-color);
    margin-bottom: 1.5rem;
    font-size: 2rem;
    position: relative;
    padding-bottom: 0.5rem;
  }

  article h2::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 100px;
    height: 4px;
    background: linear-gradient(90deg, var(--primary-color), var(--secondary-color));
    border-radius: 2px;
  }

  article h3 {
    color: var(--secondary-color);
    margin: 2rem 0 1rem;
    font-size: 1.5rem;
  }

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

  /* Code Blocks */
  pre {
    background: var(--dark-bg);
    color: white;
    padding: 1.5rem;
    border-radius: var(--border-radius);
    margin: 2rem 0;
    overflow: auto;
    box-shadow: var(--box-shadow);
  }

  code {
    font-family: 'Courier New', monospace;
    font-size: 0.9rem;
  }

  /* Feature Cards */
  .features {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
    margin: 3rem 0;
  }

  .feature-card {
    background: white;
    border-radius: var(--border-radius);
    padding: 2rem;
    box-shadow: var(--box-shadow);
    transition: var(--transition);
    position: relative;
    overflow: hidden;
  }

  .feature-card:hover {
    transform: translateY(-10px);
  }

  .feature-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 5px;
    height: 100%;
    background: linear-gradient(to bottom, var(--primary-color), var(--secondary-color));
  }

  .feature-card h3 {
    color: var(--secondary-color);
    margin-bottom: 1rem;
  }

  .feature-card p {
    margin-bottom: 1.5rem;
  }

  .feature-list {
    list-style: none;
  }

  .feature-list li {
    margin-bottom: 0.5rem;
    position: relative;
    padding-left: 1.5rem;
  }

  .feature-list li::before {
    content: '✓';
    position: absolute;
    left: 0;
    color: var(--primary-color);
    font-weight: bold;
  }

  /* Image Gallery */
  .gallery {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 1.5rem;
    margin: 3rem 0;
  }

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

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

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

  .gallery-item:hover img {
    transform: scale(1.1);
  }

  /* Footer */
  footer {
    background: var(--dark-bg);
    color: var(--light-text);
    padding: 3rem 0;
    text-align: center;
  }

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

  .footer-content p {
    margin-bottom: 1rem;
  }

  .footer-links {
    display: flex;
    justify-content: center;
    gap: 2rem;
    margin-top: 1.5rem;
  }

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

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

  /* Animations */
  @keyframes float {
    0%, 100% { transform: translateY(0); }
    50% { transform: translateY(-20px); }
  }

  .floating {
    animation: float 6s ease-in-out infinite;
  }

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

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

    article {
      padding: 2rem;
    }

    .header-content h1 {
      font-size: 2rem;
    }
  }

  /* Reference Banner */
  .reference-banner {
    background: rgba(0,0,0,0.8);
    color: white;
    padding: 1rem;
    text-align: center;
    position: fixed;
    bottom: 0;
    left: 0;
    width: 100%;
    z-index: 1000;
  }