:root {
    --primary: #001f3f;
    --secondary: #003366;
    --accent: #ff851b;
    --accent-light: #ff9933;
    --text: #ffffff;
    --card-bg: #002b5c;
    --chart-bg: #001f3f;
  }

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

  body {
    background: linear-gradient(135deg, var(--primary), var(--secondary));
    color: var(--text);
    font-family: 'Roboto', sans-serif;
    line-height: 1.6;
    overflow-x: hidden;
  }

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

  .header {
    text-align: center;
    padding: 60px 0 40px;
    position: relative;
  }

  .header::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 50%;
    transform: translateX(-50%);
    width: 200px;
    height: 3px;
    background: linear-gradient(to right, transparent, var(--accent), transparent);
  }

  h1, h2, h3 {
    color: var(--accent);
    margin-bottom: 20px;
    text-shadow: 1px 1px 2px rgba(0,0,0,0.5);
  }

  h1 {
    font-size: 2.5rem;
    background: linear-gradient(to right, var(--accent), var(--accent-light));
    -webkit-background-clip: text;
    background-clip: text;
    color: transparent;
    margin-bottom: 10px;
  }

  h2 {
    font-size: 1.8rem;
    position: relative;
    padding-bottom: 10px;
  }

  h2::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 60px;
    height: 2px;
    background: var(--accent);
  }

  h3 {
    font-size: 1.4rem;
    margin-top: 30px;
  }

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

  .grid-container {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(500px, 1fr));
    gap: 30px;
    margin: 40px 0;
  }

  .grid-item {
    background: var(--card-bg);
    padding: 30px;
    border-radius: 12px;
    box-shadow: 0 10px 20px rgba(0,0,0,0.2);
    transition: transform 0.3s, box-shadow 0.3s;
  }

  .grid-item:hover {
    transform: translateY(-5px);
    box-shadow: 0 15px 30px rgba(0,0,0,0.3);
  }

  .card {
    background: var(--card-bg);
    border-radius: 12px;
    overflow: hidden;
    transition: transform 0.3s, box-shadow 0.3s;
    position: relative;
  }

  .card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 4px;
    background: linear-gradient(to right, var(--accent), var(--accent-light));
  }

  .card:hover {
    transform: translateY(-10px);
    box-shadow: 0 15px 30px rgba(0,0,0,0.3);
  }

  .card-img {
    width: 100%;
    height: 200px;
    object-fit: cover;
    border-radius: 8px 8px 0 0;
  }

  .card-content {
    padding: 20px;
  }

  .code-container {
    background: #000;
    border-radius: 8px;
    padding: 20px;
    margin: 20px 0;
    overflow: auto;
    position: relative;
  }

  .code-container::before {
    content: 'CSS';
    position: absolute;
    top: 10px;
    right: 10px;
    color: var(--accent);
    font-size: 0.8rem;
  }

  pre {
    margin: 0;
    white-space: pre-wrap;
    font-family: 'Courier New', monospace;
    color: #f8f8f2;
    line-height: 1.5;
  }

  .btn {
    display: inline-block;
    background: linear-gradient(to right, var(--accent), var(--accent-light));
    color: #fff;
    padding: 12px 24px;
    border: none;
    border-radius: 30px;
    font-weight: bold;
    text-transform: uppercase;
    letter-spacing: 1px;
    cursor: pointer;
    transition: transform 0.2s, box-shadow 0.2s;
    box-shadow: 0 4px 6px rgba(0,0,0,0.1);
  }

  .btn:hover {
    transform: translateY(-3px);
    box-shadow: 0 8px 15px rgba(0,0,0,0.2);
  }

  .footer {
    background: var(--primary);
    padding: 40px 0;
    text-align: center;
    margin-top: 60px;
  }

  .footer p {
    margin-bottom: 0;
  }

  .reference {
    background: rgba(0,0,0,0.2);
    padding: 15px;
    border-radius: 8px;
    margin: 30px 0;
    text-align: center;
    font-style: italic;
  }

  @media (max-width: 768px) {
    .grid-container {
      grid-template-columns: 1fr;
    }
    
    h1 {
      font-size: 2rem;
    }
    
    h2 {
      font-size: 1.5rem;
    }
  }

  /* Animation */
  @keyframes float {
    0%, 100% { transform: translateY(0); }
    50% { transform: translateY(-10px); }
  }

  .floating {
    animation: float 3s ease-in-out infinite;
  }

  /* Navigation */
  .nav-links {
    display: flex;
    justify-content: center;
    flex-wrap: wrap;
    gap: 15px;
    margin: 30px 0;
  }

  .nav-link {
    color: var(--text);
    text-decoration: none;
    padding: 8px 16px;
    border-radius: 20px;
    background: rgba(255,255,255,0.1);
    transition: background 0.3s, transform 0.3s;
  }

  .nav-link:hover {
    background: rgba(255,133,27,0.2);
    transform: scale(1.05);
  }