:root {
    --primary: #FF6F61;
    --secondary: #FFD1DC;
    --accent: #5F9EA0;
    --light: #F5F5F5;
    --dark: #333333;
    --transition: all 0.3s cubic-bezier(0.25, 0.8, 0.25, 1);
  }

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

  body {
    font-family: 'Montserrat', 'Helvetica Neue', Arial, sans-serif;
    line-height: 1.6;
    color: var(--dark);
    background: linear-gradient(135deg, #FFF5F5, #FFF);
    overflow-x: hidden;
  }

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

  .hero {
    height: 60vh;
    min-height: 500px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: radial-gradient(circle at 70% 30%, var(--secondary), var(--primary));
    position: relative;
    overflow: hidden;
    margin-bottom: 80px;
    border-radius: 0 0 40px 40px;
    box-shadow: 0 10px 30px rgba(255, 111, 97, 0.2);
  }

  .hero::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: url('https://images.gptkong.com/demo/sample3.png') no-repeat center/cover;
    opacity: 0.1;
  }

  .hero-content {
    text-align: center;
    color: white;
    z-index: 1;
    padding: 0 20px;
    max-width: 800px;
  }

  .hero h1 {
    font-size: 3.5rem;
    margin-bottom: 20px;
    text-shadow: 3px 3px 10px rgba(0, 0, 0, 0.2);
    animation: fadeInUp 1s ease;
  }

  .hero p {
    font-size: 1.2rem;
    margin-bottom: 30px;
    opacity: 0.9;
    animation: fadeInUp 1s ease 0.2s forwards;
  }

  .notice {
    position: fixed;
    bottom: 20px;
    right: 20px;
    background: white;
    padding: 15px 25px;
    border-radius: 50px;
    box-shadow: 0 5px 15px rgba(0, 0, 0, 0.1);
    z-index: 1000;
    font-size: 0.9rem;
    color: var(--dark);
    animation: slideInRight 0.5s ease;
  }

  @keyframes fadeInUp {
    from {
      opacity: 0;
      transform: translateY(20px);
    }
    to {
      opacity: 1;
      transform: translateY(0);
    }
  }

  @keyframes slideInRight {
    from {
      transform: translateX(100%);
    }
    to {
      transform: translateX(0);
    }
  }

  article {
    background: white;
    border-radius: 20px;
    padding: 60px;
    margin: 0 auto 80px;
    max-width: 900px;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.05);
    position: relative;
  }

  article::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 10px;
    background: linear-gradient(90deg, var(--primary), var(--accent));
    border-radius: 20px 20px 0 0;
  }

  article h2 {
    font-size: 2.5rem;
    margin-bottom: 30px;
    color: var(--primary);
    position: relative;
    padding-bottom: 15px;
  }

  article h2::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 80px;
    height: 4px;
    background: linear-gradient(90deg, var(--primary), var(--secondary));
    border-radius: 2px;
  }

  article h3 {
    font-size: 1.8rem;
    margin: 40px 0 20px;
    color: var(--dark);
  }

  article p {
    font-size: 1.1rem;
    margin-bottom: 25px;
    line-height: 1.8;
  }

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

  .image-card {
    border-radius: 15px;
    overflow: hidden;
    box-shadow: 0 5px 15px rgba(0, 0, 0, 0.1);
    transition: var(--transition);
    position: relative;
  }

  .image-card:hover {
    transform: translateY(-10px);
    box-shadow: 0 15px 30px rgba(0, 0, 0, 0.15);
  }

  .image-card img {
    width: 100%;
    height: 300px;
    object-fit: cover;
    display: block;
  }

  pre {
    background: #2d2d2d;
    border-radius: 10px;
    padding: 20px;
    margin: 30px 0;
    overflow: auto;
    color: #f8f8f2;
    font-family: 'Courier New', Courier, monospace;
    font-size: 0.95rem;
    line-height: 1.5;
    position: relative;
  }

  pre::before {
    content: 'CSS';
    position: absolute;
    top: 0;
    left: 0;
    background: var(--primary);
    color: white;
    padding: 5px 15px;
    border-radius: 10px 0 10px 0;
    font-size: 0.8rem;
    font-weight: bold;
  }

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

  .nav-tabs {
    display: flex;
    margin: 40px 0 20px;
    border-bottom: 1px solid #eee;
  }

  .nav-tabs a {
    padding: 10px 20px;
    margin-right: 10px;
    border-radius: 5px 5px 0 0;
    background: #f5f5f5;
    color: var(--dark);
    text-decoration: none;
    transition: var(--transition);
    font-weight: 600;
  }

  .nav-tabs a:hover {
    background: #e0e0e0;
  }

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

  @media (max-width: 768px) {
    .hero h1 {
      font-size: 2.5rem;
    }
    
    article {
      padding: 40px 20px;
    }
    
    article h2 {
      font-size: 2rem;
    }
    
    article h3 {
      font-size: 1.5rem;
    }
    
    .image-grid {
      grid-template-columns: 1fr;
    }
  }