:root {
    --primary-color: #0D47A1;
    --secondary-color: #FFFFFF;
    --accent-color: #FF6F00;
    --background-color: #F5F5F5;
    --text-color: #333333;
    --light-gray: #E0E0E0;
    --dark-gray: #757575;
    --transition: all 0.3s ease;
  }

  @font-face {
    font-family: 'Roboto';
    src: url('https://fonts.googleapis.com/css2?family=Roboto:wght@400;700&display=swap');
  }

  @font-face {
    font-family: 'Open Sans';
    src: url('https://fonts.googleapis.com/css2?family=Open+Sans:wght@400;600&display=swap');
  }

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

  body {
    font-family: 'Open Sans', sans-serif;
    background-color: var(--background-color);
    color: var(--text-color);
    line-height: 1.6;
    overflow-x: hidden;
  }

  .design-notice {
    position: fixed;
    top: 20px;
    right: 20px;
    background-color: var(--accent-color);
    color: var(--secondary-color);
    padding: 8px 16px;
    border-radius: 20px;
    font-size: 14px;
    z-index: 1001;
    box-shadow: 0 4px 8px rgba(0,0,0,0.1);
    transform: rotate(5deg);
  }

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

  header {
    background: linear-gradient(135deg, var(--primary-color), #1565C0);
    color: var(--secondary-color);
    padding: 80px 0;
    text-align: center;
    position: relative;
    overflow: hidden;
  }

  header::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: radial-gradient(circle at 20% 50%, rgba(255,255,255,0.1) 0%, transparent 50%);
  }

  header h1 {
    font-family: 'Roboto', sans-serif;
    font-size: 3rem;
    margin-bottom: 20px;
    text-shadow: 0 2px 4px rgba(0,0,0,0.2);
    position: relative;
    z-index: 1;
  }

  header p {
    font-size: 1.2rem;
    max-width: 800px;
    margin: 0 auto 30px;
    position: relative;
    z-index: 1;
  }

  .header-decoration {
    position: absolute;
    width: 100%;
    height: 100%;
    top: 0;
    left: 0;
    pointer-events: none;
  }

  .decoration-circle {
    position: absolute;
    border-radius: 50%;
    background: rgba(255,255,255,0.05);
  }

  .circle-1 {
    width: 300px;
    height: 300px;
    top: -150px;
    right: -150px;
  }

  .circle-2 {
    width: 200px;
    height: 200px;
    bottom: -100px;
    left: -100px;
  }

  nav {
    position: sticky;
    top: 0;
    background-color: var(--secondary-color);
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
    z-index: 1000;
    padding: 15px 0;
  }

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

  .nav-logo {
    font-family: 'Roboto', sans-serif;
    font-weight: bold;
    font-size: 1.5rem;
    color: var(--primary-color);
    text-decoration: none;
  }

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

  .nav-links li {
    margin-left: 30px;
  }

  .nav-links a {
    color: var(--primary-color);
    text-decoration: none;
    font-weight: 600;
    position: relative;
    padding: 5px 0;
    transition: var(--transition);
  }

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

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

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

  main {
    padding: 60px 0;
  }

  section {
    margin-bottom: 80px;
    position: relative;
  }

  section::before {
    content: '';
    position: absolute;
    top: -40px;
    left: 0;
    width: 100%;
    height: 1px;
    background: linear-gradient(90deg, transparent, var(--light-gray), transparent);
  }

  h2 {
    font-family: 'Roboto', sans-serif;
    color: var(--primary-color);
    font-size: 2rem;
    margin-bottom: 30px;
    position: relative;
    display: inline-block;
  }

  h2::after {
    content: '';
    position: absolute;
    bottom: -10px;
    left: 0;
    width: 60px;
    height: 3px;
    background-color: var(--accent-color);
  }

  h3 {
    font-family: 'Roboto', sans-serif;
    color: var(--primary-color);
    font-size: 1.5rem;
    margin: 30px 0 20px;
  }

  p {
    margin-bottom: 20px;
    font-size: 1.1rem;
    line-height: 1.8;
  }

  .content-block {
    background-color: var(--secondary-color);
    border-radius: 8px;
    padding: 40px;
    box-shadow: 0 5px 15px rgba(0,0,0,0.05);
    margin-bottom: 40px;
    transition: transform 0.3s, box-shadow 0.3s;
  }

  .content-block:hover {
    transform: translateY(-5px);
    box-shadow: 0 10px 25px rgba(0,0,0,0.1);
  }

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

  .image-card {
    position: relative;
    border-radius: 8px;
    overflow: hidden;
    box-shadow: 0 4px 8px rgba(0,0,0,0.1);
    transition: var(--transition);
  }

  .image-card:hover {
    transform: scale(1.03);
    box-shadow: 0 8px 16px rgba(0,0,0,0.2);
  }

  .image-card img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    display: block;
  }

  .image-card::after {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: linear-gradient(to top, rgba(0,0,0,0.3), transparent);
  }

  pre {
    background-color: #2d2d2d;
    color: #f8f8f2;
    padding: 20px;
    border-radius: 6px;
    overflow-x: auto;
    margin: 20px 0;
    font-family: 'Courier New', monospace;
    font-size: 0.95rem;
    line-height: 1.5;
    tab-size: 4;
  }

  code {
    font-family: 'Courier New', monospace;
    background-color: rgba(0,0,0,0.05);
    padding: 2px 4px;
    border-radius: 3px;
    font-size: 0.9rem;
  }

  table {
    width: 100%;
    border-collapse: collapse;
    margin: 30px 0;
    background-color: var(--secondary-color);
    box-shadow: 0 2px 10px rgba(0,0,0,0.05);
  }

  th, td {
    padding: 12px 15px;
    text-align: left;
    border-bottom: 1px solid var(--light-gray);
  }

  th {
    background-color: var(--primary-color);
    color: var(--secondary-color);
    font-weight: 600;
  }

  tr:hover {
    background-color: rgba(0,0,0,0.02);
  }

  .btn {
    display: inline-block;
    background-color: var(--accent-color);
    color: var(--secondary-color);
    padding: 12px 24px;
    border-radius: 30px;
    text-decoration: none;
    font-weight: 600;
    transition: var(--transition);
    box-shadow: 0 4px 8px rgba(255,111,0,0.3);
    margin: 10px 0;
  }

  .btn:hover {
    background-color: #E65100;
    transform: translateY(-2px);
    box-shadow: 0 6px 12px rgba(255,111,0,0.4);
  }

  .feature-list {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 30px;
    margin: 40px 0;
  }

  .feature-item {
    background-color: var(--secondary-color);
    padding: 30px;
    border-radius: 8px;
    box-shadow: 0 5px 15px rgba(0,0,0,0.05);
    transition: var(--transition);
    position: relative;
    overflow: hidden;
  }

  .feature-item:hover {
    transform: translateY(-5px);
    box-shadow: 0 10px 25px rgba(0,0,0,0.1);
  }

  .feature-item::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 4px;
    height: 100%;
    background-color: var(--accent-color);
  }

  .feature-icon {
    font-size: 2.5rem;
    color: var(--accent-color);
    margin-bottom: 20px;
  }

  .back-to-top {
    position: fixed;
    bottom: 30px;
    right: 30px;
    width: 50px;
    height: 50px;
    background-color: var(--accent-color);
    color: var(--secondary-color);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    text-decoration: none;
    opacity: 0;
    visibility: hidden;
    transition: var(--transition);
    box-shadow: 0 4px 8px rgba(0,0,0,0.2);
    z-index: 999;
  }

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

  .back-to-top:hover {
    background-color: #E65100;
    transform: translateY(-3px);
  }

  footer {
    background-color: var(--primary-color);
    color: var(--secondary-color);
    padding: 40px 0;
    text-align: center;
  }

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

  .footer-links {
    display: flex;
    justify-content: center;
    list-style: none;
    margin: 20px 0;
  }

  .footer-links li {
    margin: 0 15px;
  }

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

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

  .copyright {
    margin-top: 20px;
    font-size: 0.9rem;
    opacity: 0.8;
  }

  @media (max-width: 768px) {
    header h1 {
      font-size: 2.2rem;
    }

    .nav-links {
      display: none;
    }

    .content-block {
      padding: 30px;
    }

    .feature-list {
      grid-template-columns: 1fr;
    }
  }

  @media (max-width: 480px) {
    header {
      padding: 60px 0;
    }

    header h1 {
      font-size: 1.8rem;
    }

    .content-block {
      padding: 20px;
    }

    h2 {
      font-size: 1.6rem;
    }

    h3 {
      font-size: 1.3rem;
    }
  }

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

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

  @keyframes pulse {
    0% { transform: scale(1); }
    50% { transform: scale(1.05); }
    100% { transform: scale(1); }
  }

  .pulse {
    animation: pulse 2s infinite;
  }

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