:root {
    --primary: #0f2027;
    --secondary: #203a43;
    --accent: #00ffcc;
    --text: #e0e0e0;
    --highlight: #ffcc00;
    --card-bg: #1e1e1e;
    --gradient: linear-gradient(135deg, var(--primary), var(--secondary), #2c5364);
  }

  * {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: 'Roboto', sans-serif;
  }

  body {
    background: var(--gradient);
    color: var(--text);
    line-height: 1.6;
    padding: 0;
    overflow-x: hidden;
    min-height: 100%;
  }

  .container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 40px 20px;
  }

  .header {
    text-align: center;
    margin-bottom: 60px;
    position: relative;
  }

  .header h1 {
    font-size: 2.8rem;
    margin-bottom: 20px;
    background: linear-gradient(90deg, var(--accent), var(--highlight));
    -webkit-background-clip: text;
    background-clip: text;
    color: transparent;
    position: relative;
    display: inline-block;
  }

  .header h1::after {
    content: '';
    position: absolute;
    bottom: -10px;
    left: 50%;
    transform: translateX(-50%);
    width: 100px;
    height: 3px;
    background: var(--accent);
    border-radius: 3px;
  }

  .notice {
    background: rgba(0,0,0,0.7);
    padding: 15px;
    border-radius: 8px;
    text-align: center;
    margin-bottom: 40px;
    border-left: 4px solid var(--highlight);
    animation: pulse 3s infinite;
  }

  @keyframes pulse {
    0% { box-shadow: 0 0 0 0 rgba(0,255,204,0.4); }
    70% { box-shadow: 0 0 0 10px rgba(0,255,204,0); }
    100% { box-shadow: 0 0 0 0 rgba(0,255,204,0); }
  }

  article {
    background: rgba(30,30,30,0.8);
    border-radius: 15px;
    padding: 40px;
    box-shadow: 0 10px 30px rgba(0,0,0,0.3);
    margin-bottom: 60px;
  }

  article h2 {
    font-size: 2rem;
    margin-bottom: 30px;
    color: var(--accent);
    position: relative;
    padding-bottom: 15px;
  }

  article h2::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 60px;
    height: 3px;
    background: var(--highlight);
  }

  article h3 {
    font-size: 1.5rem;
    margin: 30px 0 20px;
    color: var(--highlight);
  }

  article p {
    margin-bottom: 20px;
    font-size: 1.1rem;
  }

  pre {
    background: #1a1a1a;
    border-radius: 8px;
    padding: 20px;
    margin: 20px 0;
    overflow: auto;
    border-left: 4px solid var(--accent);
  }

  code {
    font-family: 'Courier New', monospace;
    color: var(--accent);
  }

  table {
    width: 100%;
    border-collapse: collapse;
    margin: 30px 0;
    background: #1a1a1a;
    border-radius: 8px;
    overflow: hidden;
  }

  th, td {
    padding: 15px;
    text-align: left;
    border-bottom: 1px solid #333;
  }

  th {
    background: var(--secondary);
    color: var(--accent);
  }

  tr:hover {
    background: rgba(0,255,204,0.1);
  }

  .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 rgba(0,0,0,0.3);
    transition: transform 0.3s, box-shadow 0.3s;
  }

  .gallery-item:hover {
    transform: translateY(-10px);
    box-shadow: 0 15px 30px rgba(0,0,0,0.4);
  }

  .gallery-item img {
    width: 100%;
    height: auto;
    display: block;
    transition: transform 0.5s;
  }

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

  .card-demo {
    background: var(--card-bg);
    border-radius: 15px;
    padding: 30px;
    margin: 40px 0;
    box-shadow: 0 10px 20px rgba(0,0,0,0.2);
    border-top: 3px solid var(--accent);
    position: relative;
    overflow: hidden;
  }

  .card-demo::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 5px;
    background: linear-gradient(90deg, var(--accent), var(--highlight));
  }

  .card-demo h4 {
    color: var(--highlight);
    margin-bottom: 20px;
    font-size: 1.3rem;
  }

  .card-demo p {
    margin-bottom: 15px;
  }

  .card-demo .price {
    font-size: 1.8rem;
    font-weight: bold;
    color: var(--accent);
  }

  .card-demo .change {
    color: #4caf50;
    font-weight: bold;
  }

  .nav-tabs {
    display: flex;
    margin-bottom: 30px;
    border-bottom: 1px solid #333;
  }

  .nav-tabs a {
    padding: 15px 25px;
    text-decoration: none;
    color: var(--text);
    position: relative;
    transition: color 0.3s;
  }

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

  .nav-tabs a.active {
    color: var(--accent);
  }

  .nav-tabs a.active::after {
    content: '';
    position: absolute;
    bottom: -1px;
    left: 0;
    width: 100%;
    height: 3px;
    background: var(--accent);
  }

  @media (max-width: 768px) {
    .container {
      padding: 20px 15px;
    }
    
    article {
      padding: 25px;
    }
    
    .header h1 {
      font-size: 2rem;
    }
    
    .gallery {
      grid-template-columns: 1fr;
    }
  }

  /* Particle animation */
  .particles {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    z-index: -1;
    overflow: hidden;
  }

  .particle {
    position: absolute;
    background: rgba(255, 255, 255, 0.6);
    border-radius: 50%;
    animation: float 6s infinite ease-in-out;
  }

  @keyframes float {
    0% { transform: translate(0, 0); opacity: 0.5; }
    50% { transform: translate(20px, -20px); opacity: 1; }
    100% { transform: translate(-20px, 20px); opacity: 0.5; }
  }