:root {
    --primary: #0E2A47;
    --secondary: #F5DEB3;
    --accent: #D3D3D3;
    --text: #333;
    --light: #fff;
    --shadow: 0 4px 20px rgba(0,0,0,0.1);
    --transition: all 0.3s ease;
  }

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

  body {
    font-family: 'Helvetica Neue', Arial, sans-serif;
    line-height: 1.6;
    color: var(--text);
    background: linear-gradient(135deg, var(--secondary) 0%, #f8f4e8 100%);
    min-height: 100%;
    overflow-x: hidden;
  }

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

  header {
    background: var(--primary);
    color: var(--light);
    padding: 30px 0;
    text-align: center;
    position: relative;
    overflow: hidden;
  }

  header::after {
    content: '';
    position: absolute;
    bottom: -50px;
    left: 0;
    width: 100%;
    height: 100px;
    background: linear-gradient(to bottom, var(--primary) 0%, transparent 100%);
    z-index: 1;
  }

  h1 {
    font-size: 2.5rem;
    margin-bottom: 15px;
    position: relative;
    z-index: 2;
    text-shadow: 0 2px 4px rgba(0,0,0,0.3);
  }

  .tagline {
    font-size: 1.2rem;
    opacity: 0.9;
    position: relative;
    z-index: 2;
  }

  .hero {
    height: 400px;
    background: url('https://images.gptkong.com/demo/sample1.png') center/cover no-repeat;
    border-radius: 20px;
    margin: 40px 0;
    box-shadow: var(--shadow);
    position: relative;
    overflow: hidden;
  }

  .hero::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: linear-gradient(45deg, rgba(14,42,71,0.7) 0%, rgba(245,222,179,0.3) 100%);
  }

  .notice {
    background: var(--light);
    padding: 20px;
    border-radius: 10px;
    margin: 30px 0;
    text-align: center;
    box-shadow: var(--shadow);
    font-weight: bold;
    color: var(--primary);
  }

  article {
    background: var(--light);
    border-radius: 20px;
    padding: 40px;
    margin: 40px 0;
    box-shadow: var(--shadow);
  }

  h2 {
    color: var(--primary);
    font-size: 1.8rem;
    margin: 30px 0 20px;
    position: relative;
    padding-bottom: 10px;
  }

  h2::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 100px;
    height: 3px;
    background: linear-gradient(90deg, var(--primary) 0%, var(--accent) 100%);
  }

  h3 {
    color: var(--primary);
    font-size: 1.4rem;
    margin: 25px 0 15px;
  }

  p {
    margin-bottom: 20px;
    font-size: 1.1rem;
    line-height: 1.7;
  }

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

  .image-card {
    background: var(--light);
    border-radius: 15px;
    overflow: hidden;
    box-shadow: var(--shadow);
    transition: var(--transition);
  }

  .image-card:hover {
    transform: translateY(-10px);
    box-shadow: 0 10px 30px rgba(0,0,0,0.15);
  }

  .image-card img {
    width: 100%;
    height: 200px;
    object-fit: cover;
    border-bottom: 1px solid rgba(0,0,0,0.1);
  }

  .image-card p {
    padding: 15px;
    font-size: 0.9rem;
    color: var(--text);
  }

  pre {
    background: #f5f5f5;
    border-radius: 10px;
    padding: 20px;
    margin: 20px 0;
    overflow-x: auto;
    font-family: 'Courier New', monospace;
    border-left: 4px solid var(--primary);
  }

  code {
    font-family: 'Courier New', monospace;
    color: #d63384;
  }

  .nav-tabs {
    display: flex;
    list-style: none;
    margin: 30px 0;
    background: var(--light);
    border-radius: 10px;
    overflow: hidden;
    box-shadow: var(--shadow);
  }

  .nav-tabs li {
    flex: 1;
    text-align: center;
  }

  .nav-tabs a {
    display: block;
    padding: 15px;
    color: var(--primary);
    text-decoration: none;
    font-weight: bold;
    transition: var(--transition);
  }

  .nav-tabs a:hover {
    background: rgba(14,42,71,0.1);
  }

  .nav-tabs a.active {
    background: var(--primary);
    color: var(--light);
  }

  .accordion {
    margin: 30px 0;
  }

  .accordion-item {
    margin-bottom: 10px;
    border-radius: 10px;
    overflow: hidden;
    box-shadow: var(--shadow);
  }

  .accordion-header {
    background: var(--primary);
    color: var(--light);
    padding: 15px 20px;
    cursor: pointer;
    display: flex;
    justify-content: space-between;
    align-items: center;
    transition: var(--transition);
  }

  .accordion-header:hover {
    background: #0a1f36;
  }

  .accordion-content {
    background: var(--light);
    padding: 0;
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.3s ease;
  }

  .accordion-content-inner {
    padding: 20px;
  }

  .accordion-item.active .accordion-content {
    max-height: 1000px;
  }

  footer {
    background: var(--primary);
    color: var(--light);
    padding: 30px 0;
    text-align: center;
    margin-top: 50px;
  }

  @media (max-width: 768px) {
    h1 {
      font-size: 2rem;
    }
    
    .hero {
      height: 300px;
    }
    
    article {
      padding: 20px;
    }
    
    .image-grid {
      grid-template-columns: 1fr;
    }
  }