@import url('https://fonts.googleapis.com/css2?family=Orbitron:wght@400;700&family=Roboto:wght@300;400;500;700&display=swap');
  
  :root {
    --primary: #0f2027;
    --secondary: #203a43;
    --accent: #00CED1;
    --highlight: #00ffcc;
    --text: #ffffff;
    --card-bg: #1e1e1e;
    --shadow: rgba(0,0,0,0.2);
  }
  
  * {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
  }
  
  body {
    background: linear-gradient(135deg, var(--primary), var(--secondary), #2c5364);
    color: var(--text);
    font-family: 'Roboto', sans-serif;
    line-height: 1.6;
    letter-spacing: 0.5px;
    padding: 0;
    overflow-x: hidden;
  }
  
  .container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 20px;
  }
  
  .header {
    text-align: center;
    padding: 40px 0;
    position: relative;
    overflow: hidden;
  }
  
  .header::before {
    content: "";
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: url('https://images.gptkong.com/demo/sample1.png') center/cover no-repeat;
    opacity: 0.2;
    z-index: -1;
  }
  
  h1, h2, h3, h4 {
    font-family: 'Orbitron', sans-serif;
    margin-bottom: 20px;
    color: var(--highlight);
  }
  
  h1 {
    font-size: 2.5rem;
    background: linear-gradient(90deg, var(--highlight), var(--accent));
    -webkit-background-clip: text;
    background-clip: text;
    color: transparent;
    text-shadow: 0 0 10px rgba(0,255,204,0.3);
  }
  
  h2 {
    font-size: 1.9rem;
    border-bottom: 2px solid var(--accent);
    padding-bottom: 10px;
    margin-top: 40px;
  }
  
  h3 {
    font-size: 1.6rem;
    margin-top: 30px;
    color: var(--accent);
  }
  
  p {
    margin-bottom: 20px;
    font-size: 1.1rem;
  }
  
  strong {
    color: var(--highlight);
  }
  
  .grid-system {
    display: grid;
    grid-template-columns: repeat(12, 1fr);
    gap: 30px;
    margin: 40px 0;
  }
  
  .card {
    background: var(--card-bg);
    padding: 30px;
    border-radius: 15px;
    box-shadow: 0 10px 20px var(--shadow);
    transition: transform 0.3s, box-shadow 0.3s;
    position: relative;
    overflow: hidden;
  }
  
  .card:hover {
    transform: translateY(-10px);
    box-shadow: 0 15px 30px rgba(0,206,209,0.3);
  }
  
  .card::after {
    content: "";
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 5px;
    background: linear-gradient(90deg, var(--accent), var(--highlight));
  }
  
  .main-content {
    grid-column: span 8;
  }
  
  .sidebar {
    grid-column: span 4;
  }
  
  pre {
    background: #1a2a32;
    padding: 20px;
    border-radius: 10px;
    overflow-x: auto;
    margin: 20px 0;
    border-left: 4px solid var(--accent);
    font-family: 'Roboto Mono', monospace;
    position: relative;
  }
  
  pre::before {
    content: "CSS";
    position: absolute;
    top: 0;
    right: 0;
    background: var(--accent);
    color: var(--primary);
    padding: 2px 10px;
    font-size: 0.8rem;
    border-bottom-left-radius: 5px;
  }
  
  code {
    color: var(--highlight);
    font-family: 'Roboto Mono', monospace;
  }
  
  table {
    width: 100%;
    border-collapse: collapse;
    margin: 30px 0;
    background: var(--card-bg);
    border-radius: 10px;
    overflow: hidden;
  }
  
  th, td {
    padding: 15px;
    text-align: left;
    border-bottom: 1px solid var(--secondary);
  }
  
  th {
    background: var(--secondary);
    color: var(--highlight);
  }
  
  tr:hover {
    background: rgba(0,206,209,0.1);
  }
  
  .image-gallery {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
    gap: 20px;
    margin: 40px 0;
  }
  
  .gallery-item {
    border-radius: 10px;
    overflow: hidden;
    box-shadow: 0 5px 15px var(--shadow);
    transition: transform 0.3s;
    position: relative;
  }
  
  .gallery-item:hover {
    transform: scale(1.03);
  }
  
  .gallery-item img {
    width: 100%;
    height: auto;
    display: block;
    transition: transform 0.5s;
  }
  
  .gallery-item:hover img {
    transform: scale(1.1);
  }
  
  .notice {
    background: rgba(0,206,209,0.1);
    border-left: 4px solid var(--accent);
    padding: 20px;
    margin: 40px 0;
    border-radius: 0 10px 10px 0;
  }
  
  .notice p {
    margin: 0;
  }
  
  .particles {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    pointer-events: none;
    z-index: -1;
  }
  
  .particle {
    width: 8px;
    height: 8px;
    background: var(--highlight);
    border-radius: 50%;
    position: absolute;
    opacity: 0.5;
    animation: move 15s infinite linear;
  }
  
  @keyframes move {
    0% { transform: translate(0, 0); }
    100% { transform: translate(calc(100vw * var(--x)), calc(100vh * var(--y))); }
  }
  
  .button {
    display: inline-block;
    background: linear-gradient(45deg, var(--accent), var(--highlight));
    color: var(--primary);
    padding: 12px 25px;
    border-radius: 30px;
    text-decoration: none;
    font-weight: 500;
    margin: 10px 0;
    box-shadow: 0 5px 15px rgba(0,206,209,0.3);
    transition: transform 0.3s, box-shadow 0.3s;
    border: none;
    cursor: pointer;
  }
  
  .button:hover {
    transform: translateY(-3px);
    box-shadow: 0 8px 20px rgba(0,206,209,0.4);
  }
  
  .chart-container {
    background: var(--card-bg);
    padding: 30px;
    border-radius: 15px;
    margin: 40px 0;
    position: relative;
    overflow: hidden;
  }
  
  .chart-container::before {
    content: "";
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: url('https://images.gptkong.com/demo/sample3.png') center/cover no-repeat;
    opacity: 0.1;
    z-index: 0;
  }
  
  .chart-content {
    position: relative;
    z-index: 1;
  }
  
  @media (max-width: 768px) {
    .grid-system {
      grid-template-columns: 1fr;
    }
    
    .main-content, .sidebar {
      grid-column: span 1;
    }
    
    h1 {
      font-size: 2rem;
    }
    
    h2 {
      font-size: 1.6rem;
    }
    
    h3 {
      font-size: 1.3rem;
    }
  }
  
  .footer {
    text-align: center;
    padding: 40px 0;
    margin-top: 60px;
    border-top: 1px solid var(--secondary);
  }
  
  .nav-links {
    display: flex;
    justify-content: center;
    flex-wrap: wrap;
    gap: 20px;
    margin-bottom: 30px;
  }
  
  .nav-link {
    color: var(--text);
    text-decoration: none;
    transition: color 0.3s;
    position: relative;
  }
  
  .nav-link:hover {
    color: var(--highlight);
  }
  
  .nav-link::after {
    content: "";
    position: absolute;
    bottom: -5px;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--highlight);
    transition: width 0.3s;
  }
  
  .nav-link:hover::after {
    width: 100%;
  }