:root {
    --primary-dark: #1E2D4A;
    --primary-light: #00B4FF;
    --accent: #39CFC7;
    --neutral: #F2F2F2;
    --text-dark: #333333;
    --text-light: #FFFFFF;
    --shadow: 0 10px 30px rgba(0, 0, 0, 0.1);
    --transition: all 0.4s cubic-bezier(0.175, 0.885, 0.32, 1.275);
  }

  @font-face {
    font-family: 'Roboto';
    src: local('Roboto Bold'), local('Roboto-Bold');
    font-weight: 700;
    font-style: normal;
  }

  @font-face {
    font-family: 'Open Sans';
    src: local('Open Sans Regular'), local('OpenSans-Regular');
    font-weight: 400;
    font-style: normal;
  }

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

  body {
    font-family: 'Open Sans', sans-serif;
    color: var(--text-dark);
    background-color: var(--neutral);
    line-height: 1.7;
    overflow-x: hidden;
  }

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

  /* Header Styles */
  .header {
    position: relative;
    height: 600px;
    overflow: hidden;
    display: flex;
    align-items: center;
    justify-content: center;
    background: linear-gradient(135deg, var(--primary-dark), var(--primary-light));
    color: var(--text-light);
    text-align: center;
    padding: 0 20px;
  }

  .header::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: url('https://images.gptkong.com/demo/sample1.png') no-repeat center center;
    background-size: cover;
    opacity: 0.1;
    z-index: 1;
  }

  .header-content {
    position: relative;
    z-index: 2;
    max-width: 800px;
  }

  .header h1 {
    font-family: 'Roboto', sans-serif;
    font-size: 3.5rem;
    margin-bottom: 20px;
    text-shadow: 0 2px 10px rgba(0, 0, 0, 0.3);
  }

  .header p {
    font-size: 1.2rem;
    margin-bottom: 30px;
  }

  .scroll-indicator {
    position: absolute;
    bottom: 30px;
    left: 50%;
    transform: translateX(-50%);
    animation: bounce 2s infinite;
  }

  @keyframes bounce {
    0%, 20%, 50%, 80%, 100% { transform: translateY(0) translateX(-50%); }
    40% { transform: translateY(-20px) translateX(-50%); }
    60% { transform: translateY(-10px) translateX(-50%); }
  }

  /* Navigation */
  .navbar {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    background-color: rgba(30, 45, 74, 0.9);
    padding: 15px 0;
    z-index: 1000;
    transition: var(--transition);
    backdrop-filter: blur(10px);
  }

  .navbar:hover {
    background-color: rgba(30, 45, 74, 0.98);
  }

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

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

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

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

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

  .nav-links a {
    color: var(--text-light);
    text-decoration: none;
    font-family: 'Open Sans', sans-serif;
    font-weight: 600;
    transition: var(--transition);
    position: relative;
  }

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

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

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

  /* Main Content */
  .main-content {
    padding: 100px 0;
  }

  .section {
    margin-bottom: 100px;
    position: relative;
  }

  .section-title {
    font-family: 'Roboto', sans-serif;
    color: var(--primary-dark);
    font-size: 2.5rem;
    margin-bottom: 40px;
    text-align: center;
    position: relative;
  }

  .section-title::after {
    content: '';
    position: absolute;
    bottom: -15px;
    left: 50%;
    transform: translateX(-50%);
    width: 80px;
    height: 4px;
    background: linear-gradient(90deg, var(--primary-light), var(--accent));
    border-radius: 2px;
  }

  .content-block {
    background-color: var(--text-light);
    border-radius: 10px;
    padding: 40px;
    margin-bottom: 40px;
    box-shadow: var(--shadow);
    transition: var(--transition);
  }

  .content-block:hover {
    transform: translateY(-5px);
    box-shadow: 0 15px 35px rgba(0, 0, 0, 0.15);
  }

  .content-block h3 {
    font-family: 'Roboto', sans-serif;
    color: var(--primary-dark);
    font-size: 1.8rem;
    margin-bottom: 20px;
  }

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

  .content-block img {
    width: 100%;
    border-radius: 8px;
    margin: 20px 0;
    box-shadow: 0 5px 15px rgba(0, 0, 0, 0.1);
    transition: var(--transition);
  }

  .content-block img:hover {
    transform: scale(1.02);
    box-shadow: 0 10px 25px rgba(0, 0, 0, 0.2);
  }

  /* Code Blocks */
  pre {
    background-color: #2d2d2d;
    border-radius: 8px;
    padding: 20px;
    margin: 20px 0;
    overflow: auto;
    position: relative;
  }

  pre::before {
    content: 'CSS';
    position: absolute;
    top: 0;
    left: 0;
    background-color: var(--accent);
    color: var(--text-light);
    padding: 5px 15px;
    border-radius: 8px 0 8px 0;
    font-family: 'Roboto', sans-serif;
    font-size: 0.9rem;
  }

  code {
    font-family: 'Courier New', monospace;
    color: #f8f8f2;
    font-size: 0.95rem;
    line-height: 1.5;
  }

  /* Image Grid */
  .image-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
    gap: 20px;
    margin: 40px 0;
  }

  .grid-item {
    position: relative;
    overflow: hidden;
    border-radius: 10px;
    box-shadow: var(--shadow);
    transition: var(--transition);
  }

  .grid-item:hover {
    transform: translateY(-5px);
    box-shadow: 0 15px 35px rgba(0, 0, 0, 0.2);
  }

  .grid-item img {
    width: 100%;
    height: 300px;
    object-fit: cover;
    transition: var(--transition);
  }

  .grid-item:hover img {
    transform: scale(1.1);
  }

  /* Footer */
  .footer {
    background-color: var(--primary-dark);
    color: var(--text-light);
    padding: 60px 0 30px;
    text-align: center;
  }

  .footer p {
    margin-bottom: 20px;
  }

  .footer-links {
    display: flex;
    justify-content: center;
    list-style: none;
    margin-bottom: 30px;
  }

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

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

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

  .copyright {
    font-size: 0.9rem;
    opacity: 0.8;
  }

  /* Responsive */
  @media (max-width: 768px) {
    .header h1 {
      font-size: 2.5rem;
    }

    .header p {
      font-size: 1rem;
    }

    .nav-container {
      flex-direction: column;
    }

    .nav-links {
      margin-top: 15px;
    }

    .nav-links li {
      margin-left: 15px;
    }

    .section-title {
      font-size: 2rem;
    }

    .content-block {
      padding: 30px;
    }

    .image-grid {
      grid-template-columns: repeat(auto-fill, minmax(250px, 1fr));
    }
  }

  @media (max-width: 480px) {
    .header {
      height: 500px;
    }

    .header h1 {
      font-size: 2rem;
    }

    .nav-links {
      flex-wrap: wrap;
      justify-content: center;
    }

    .nav-links li {
      margin: 5px 10px;
    }

    .content-block {
      padding: 20px;
    }

    .image-grid {
      grid-template-columns: 1fr;
    }
  }

  /* Special Notice */
  .notice {
    position: fixed;
    bottom: 20px;
    left: 20px;
    background-color: var(--accent);
    color: var(--text-light);
    padding: 10px 15px;
    border-radius: 5px;
    z-index: 1000;
    box-shadow: 0 5px 15px rgba(0, 0, 0, 0.2);
    animation: fadeIn 1s ease;
  }

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