:root {
    --primary: #1e3c72;
    --secondary: #2a5298;
    --accent: #e67e22;
    --dark: #333333;
    --light: #f0f4f8;
    --white: #ffffff;
    --radius: 10px;
    --shadow: 0 4px 15px rgba(0, 0, 0, 0.1);
    --transition: all 0.3s ease;
  }

  @import url('https://fonts.googleapis.com/css2?family=Roboto:wght@300;400;500;700&family=Orbitron:wght@400;500;700&display=swap');

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

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

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

  /* Header */
  .header {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    background: rgba(30, 60, 114, 0.95);
    color: var(--white);
    padding: 15px 0;
    z-index: 1000;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.2);
    transition: var(--transition);
  }

  .header.scrolled {
    background: rgba(30, 60, 114, 1);
  }

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

  .logo {
    font-family: 'Orbitron', sans-serif;
    font-weight: 700;
    font-size: 1.5rem;
    color: var(--white);
    text-decoration: none;
  }

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

  .nav-link {
    color: var(--white);
    text-decoration: none;
    font-weight: 500;
    transition: var(--transition);
    position: relative;
  }

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

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

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

  /* Hero Section */
  .hero {
    min-height: 600px;
    display: flex;
    align-items: center;
    background: linear-gradient(135deg, var(--primary), var(--secondary), #8e44ad, var(--accent));
    background-size: 400% 400%;
    animation: gradientAnimation 15s ease infinite;
    color: var(--white);
    padding: 100px 0;
    margin-top: 70px;
  }

  @keyframes gradientAnimation {
    0% { background-position: 0% 50%; }
    50% { background-position: 100% 50%; }
    100% { background-position: 0% 50%; }
  }

  .hero-content {
    max-width: 600px;
  }

  .hero-title {
    font-family: 'Orbitron', sans-serif;
    font-size: 2.5rem;
    margin-bottom: 20px;
    text-shadow: 0 2px 5px rgba(0, 0, 0, 0.3);
  }

  .hero-subtitle {
    font-size: 1.2rem;
    margin-bottom: 30px;
    opacity: 0.9;
  }

  .hero-image {
    position: absolute;
    right: 10%;
    top: 50%;
    transform: translateY(-50%);
    width: 400px;
    height: 400px;
    border-radius: 50%;
    overflow: hidden;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.3);
  }

  .hero-image img {
    width: 100%;
    height: 100%;
    object-fit: cover;
  }

  /* Main Content */
  .main {
    padding: 80px 0;
  }

  .section {
    margin-bottom: 80px;
  }

  .section-title {
    font-family: 'Orbitron', sans-serif;
    color: var(--secondary);
    font-size: 2rem;
    margin-bottom: 40px;
    position: relative;
    display: inline-block;
  }

  .section-title::after {
    content: '';
    position: absolute;
    bottom: -10px;
    left: 0;
    width: 50%;
    height: 3px;
    background: var(--accent);
    border-radius: 3px;
  }

  .grid-container {
    display: grid;
    grid-template-columns: repeat(12, 1fr);
    gap: 30px;
  }

  .col-6 {
    grid-column: span 6;
  }

  .card {
    background: var(--white);
    border-radius: var(--radius);
    box-shadow: var(--shadow);
    padding: 30px;
    transition: var(--transition);
  }

  .card:hover {
    transform: translateY(-10px);
    box-shadow: 0 10px 25px rgba(0, 0, 0, 0.2);
  }

  .card-title {
    font-family: 'Orbitron', sans-serif;
    color: var(--secondary);
    margin-bottom: 15px;
    font-size: 1.5rem;
  }

  .card-image {
    width: 100%;
    height: 200px;
    object-fit: cover;
    border-radius: var(--radius);
    margin-bottom: 20px;
    box-shadow: 0 4px 10px rgba(0, 0, 0, 0.1);
  }

  /* Code Blocks */
  pre {
    background: #282c34;
    border-radius: var(--radius);
    padding: 20px;
    margin: 20px 0;
    overflow-x: auto;
    box-shadow: var(--shadow);
  }

  code {
    font-family: 'Courier New', monospace;
    color: #abb2bf;
    font-size: 0.9rem;
  }

  /* Buttons */
  .btn {
    display: inline-block;
    background: var(--secondary);
    color: var(--white);
    padding: 12px 25px;
    border-radius: 25px;
    text-decoration: none;
    font-weight: 500;
    transition: var(--transition);
    border: none;
    cursor: pointer;
    box-shadow: 0 4px 10px rgba(0, 0, 0, 0.1);
  }

  .btn:hover {
    background: var(--primary);
    transform: translateY(-3px);
    box-shadow: 0 6px 15px rgba(0, 0, 0, 0.2);
  }

  .btn-accent {
    background: var(--accent);
  }

  .btn-accent:hover {
    background: #d35400;
  }

  /* Footer */
  .footer {
    background: var(--primary);
    color: var(--white);
    padding: 50px 0 20px;
    text-align: center;
  }

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

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

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

  .copyright {
    opacity: 0.7;
    font-size: 0.9rem;
  }

  /* Responsive */
  @media (max-width: 1024px) {
    .hero-image {
      width: 300px;
      height: 300px;
    }
  }

  @media (max-width: 768px) {
    .grid-container {
      grid-template-columns: 1fr;
    }

    .col-6 {
      grid-column: span 1;
    }

    .hero {
      flex-direction: column;
      text-align: center;
      padding: 80px 0;
    }

    .hero-content {
      margin-bottom: 40px;
    }

    .hero-image {
      position: relative;
      right: auto;
      top: auto;
      transform: none;
      margin: 0 auto;
    }

    .nav-links {
      display: none;
    }
  }

  @media (max-width: 480px) {
    .hero-title {
      font-size: 2rem;
    }

    .hero-subtitle {
      font-size: 1rem;
    }

    .section-title {
      font-size: 1.5rem;
    }

    .card {
      padding: 20px;
    }
  }

  /* Reference Banner */
  .reference-banner {
    position: fixed;
    bottom: 20px;
    right: 20px;
    background: var(--white);
    color: var(--dark);
    padding: 10px 15px;
    border-radius: var(--radius);
    box-shadow: var(--shadow);
    z-index: 1000;
    font-size: 0.8rem;
  }