:root {
    --primary: #0D1B2A;
    --secondary: #3C4858;
    --accent: #6FDEFF;
    --highlight: #57E590;
    --text: rgba(255,255,255,0.9);
    --card-bg: rgba(255,255,255,0.05);
  }

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

  @font-face {
    font-family: 'Helvetica Neue';
    src: local('Helvetica Neue');
  }

  @font-face {
    font-family: 'Lora';
    src: local('Lora');
  }

  body {
    font-family: 'Lora', serif;
    color: var(--text);
    background: var(--primary);
    line-height: 1.6;
    overflow-x: hidden;
  }

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

  /* Header Styles */
  header {
    background: linear-gradient(135deg, var(--primary), var(--secondary));
    padding: 2rem 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: 0.1;
    z-index: 0;
  }

  .header-content {
    position: relative;
    z-index: 1;
    text-align: center;
  }

  h1, h2, h3, h4 {
    font-family: 'Helvetica Neue', sans-serif;
    margin-bottom: 1.5rem;
    color: var(--accent);
  }

  h1 {
    font-size: 2.8rem;
    background: linear-gradient(90deg, var(--accent), var(--highlight));
    -webkit-background-clip: text;
    background-clip: text;
    color: transparent;
    text-shadow: 0 2px 10px rgba(0,0,0,0.3);
  }

  h2 {
    font-size: 2rem;
    position: relative;
    padding-bottom: 0.5rem;
  }

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

  h3 {
    font-size: 1.5rem;
    color: var(--highlight);
  }

  /* Navigation */
  nav {
    display: flex;
    justify-content: center;
    margin: 2rem 0;
    flex-wrap: wrap;
  }

  nav a {
    color: var(--text);
    text-decoration: none;
    margin: 0 1rem;
    padding: 0.5rem 1rem;
    border-radius: 4px;
    transition: all 0.3s ease;
    position: relative;
  }

  nav a::after {
    content: "";
    position: absolute;
    bottom: 0;
    left: 50%;
    transform: translateX(-50%);
    width: 0;
    height: 2px;
    background: var(--highlight);
    transition: width 0.3s ease;
  }

  nav a:hover {
    color: var(--highlight);
  }

  nav a:hover::after {
    width: 100%;
  }

  /* Main Content */
  main {
    padding: 3rem 0;
  }

  article {
    background: var(--card-bg);
    border-radius: 12px;
    padding: 2rem;
    margin-bottom: 3rem;
    box-shadow: 0 10px 30px rgba(0,0,0,0.2);
    transition: transform 0.3s ease;
  }

  article:hover {
    transform: translateY(-5px);
  }

  p {
    margin-bottom: 1.5rem;
    font-size: 1.1rem;
  }

  /* Code Blocks */
  pre {
    background: rgba(0,0,0,0.3);
    border-left: 4px solid var(--highlight);
    border-radius: 6px;
    padding: 1.5rem;
    margin: 2rem 0;
    overflow: auto;
    font-family: monospace;
    font-size: 0.9rem;
    line-height: 1.5;
  }

  code {
    background: rgba(0,0,0,0.3);
    padding: 0.2rem 0.4rem;
    border-radius: 3px;
    font-family: monospace;
    color: var(--highlight);
  }

  /* Grid Layout */
  .grid-container {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
    margin: 3rem 0;
  }

  .grid-item {
    background: var(--card-bg);
    border-radius: 10px;
    padding: 1.5rem;
    transition: all 0.3s ease;
    position: relative;
    overflow: hidden;
  }

  .grid-item::before {
    content: "";
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: linear-gradient(135deg, rgba(111,222,255,0.1), transparent);
    z-index: 0;
  }

  .grid-item:hover {
    transform: translateY(-5px);
    box-shadow: 0 10px 20px rgba(0,0,0,0.3);
  }

  .grid-item img {
    width: 100%;
    border-radius: 8px;
    margin-bottom: 1rem;
    transition: transform 0.3s ease;
  }

  .grid-item:hover img {
    transform: scale(1.05);
  }

  /* Parallax Section */
  .parallax {
    height: 400px;
    background-attachment: fixed;
    background-position: center;
    background-repeat: no-repeat;
    background-size: cover;
    position: relative;
    margin: 3rem 0;
    border-radius: 12px;
    overflow: hidden;
  }

  .parallax::before {
    content: "";
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: linear-gradient(135deg, rgba(13,27,42,0.7), rgba(60,72,88,0.7));
  }

  .parallax-content {
    position: relative;
    z-index: 1;
    padding: 2rem;
    color: white;
    height: 100%;
    display: flex;
    flex-direction: column;
    justify-content: center;
  }

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

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

  @keyframes pulse {
    0%, 100% { opacity: 1; }
    50% { opacity: 0.5; }
  }

  .pulsing {
    animation: pulse 2s ease-in-out infinite;
  }

  /* Footer */
  footer {
    background: linear-gradient(135deg, var(--secondary), var(--primary));
    padding: 2rem 0;
    text-align: center;
    position: relative;
  }

  footer::before {
    content: "";
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: url('https://images.gptkong.com/demo/sample12.png') center/cover no-repeat;
    opacity: 0.1;
    z-index: 0;
  }

  .footer-content {
    position: relative;
    z-index: 1;
  }

  .notice {
    background: rgba(255,255,255,0.1);
    padding: 1rem;
    border-radius: 8px;
    margin: 2rem auto;
    max-width: 800px;
    border-left: 4px solid var(--highlight);
  }

  /* Responsive Adjustments */
  @media (max-width: 768px) {
    h1 {
      font-size: 2rem;
    }
    
    h2 {
      font-size: 1.5rem;
    }
    
    .grid-container {
      grid-template-columns: 1fr;
    }
    
    .parallax {
      height: 300px;
      background-attachment: scroll;
    }
  }

  /* Special Elements */
  .door-container {
    perspective: 1000px;
    margin: 3rem auto;
    width: 200px;
    height: 300px;
  }

  .door {
    width: 100%;
    height: 100%;
    background: linear-gradient(135deg, var(--secondary), var(--primary));
    transform-style: preserve-3d;
    transform-origin: left;
    position: relative;
    transition: transform 1s ease;
    border-radius: 0 8px 8px 0;
    box-shadow: 5px 0 15px rgba(0,0,0,0.3);
  }

  .door:hover {
    transform: rotateY(-60deg);
  }

  .door::before {
    content: "";
    position: absolute;
    top: 50%;
    left: 10px;
    width: 20px;
    height: 20px;
    background: var(--highlight);
    border-radius: 50%;
    transform: translateY(-50%);
  }

  .geometry-shape {
    width: 100px;
    height: 100px;
    background: var(--accent);
    border-radius: 20% 50% 30% 70%;
    margin: 2rem auto;
    filter: drop-shadow(0 5px 15px rgba(111,222,255,0.3));
    transition: all 0.5s ease;
  }

  .geometry-shape:hover {
    border-radius: 50%;
    transform: rotate(180deg) scale(1.2);
    background: var(--highlight);
  }