:root {
    --primary-color: #3A80BA;
    --secondary-color: rgba(255, 255, 255, 0.8);
    --accent-color: #FFA500;
    --highlight-color: #FFD700;
    --bg-gradient: linear-gradient(135deg, #f5f7fa 0%, #c3cfe2 100%);
    --card-shadow: 0 8px 32px 0 rgba(31, 38, 135, 0.37);
    --text-color: #2c3e50;
  }

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

  body {
    font-family: 'Roboto', sans-serif;
    line-height: 1.6;
    color: var(--text-color);
    background: var(--bg-gradient);
    min-height: 100%;
    padding: 20px;
  }

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

  .header {
    text-align: center;
    margin-bottom: 40px;
    position: relative;
  }

  .header::after {
    content: "";
    display: block;
    width: 100px;
    height: 4px;
    background: linear-gradient(90deg, var(--primary-color), var(--accent-color));
    margin: 20px auto;
    border-radius: 2px;
  }

  h1, h2, h3, h4 {
    color: var(--primary-color);
    margin-bottom: 20px;
    font-weight: 700;
  }

  h1 {
    font-size: 2.5rem;
    background: linear-gradient(90deg, var(--primary-color), var(--accent-color));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    text-shadow: 0 2px 4px rgba(0,0,0,0.1);
  }

  h2 {
    font-size: 1.8rem;
    position: relative;
    padding-left: 15px;
  }

  h2::before {
    content: "";
    position: absolute;
    left: 0;
    top: 5px;
    height: 80%;
    width: 5px;
    background: var(--accent-color);
    border-radius: 3px;
  }

  h3 {
    font-size: 1.5rem;
    margin-top: 30px;
  }

  p {
    margin-bottom: 20px;
    font-size: 1.1rem;
    line-height: 1.8;
  }

  .glass-card {
    background: rgba(255, 255, 255, 0.25);
    border-radius: 15px;
    backdrop-filter: blur(10px);
    box-shadow: var(--card-shadow);
    border: 1px solid rgba(255, 255, 255, 0.18);
    padding: 30px;
    margin-bottom: 30px;
    transition: transform 0.3s ease, box-shadow 0.3s ease;
  }

  .glass-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 12px 40px 0 rgba(31, 38, 135, 0.45);
  }

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

  .grid-item {
    position: relative;
    overflow: hidden;
    border-radius: 15px;
    height: 320px;
  }

  .grid-item img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: transform 0.5s ease;
  }

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

  .grid-item::after {
    content: "";
    position: absolute;
    bottom: 0;
    left: 0;
    right: 0;
    height: 50%;
    background: linear-gradient(to top, rgba(0,0,0,0.7), transparent);
  }

  pre {
    background: rgba(0,0,0,0.8);
    border-radius: 10px;
    padding: 20px;
    margin: 20px 0;
    overflow-x: auto;
    color: #f8f8f2;
    font-family: 'Courier New', monospace;
    font-size: 0.9rem;
    line-height: 1.5;
    box-shadow: 0 4px 6px rgba(0,0,0,0.1);
  }

  code {
    font-family: 'Courier New', monospace;
    background: rgba(0,0,0,0.1);
    padding: 2px 5px;
    border-radius: 3px;
    color: var(--primary-color);
  }

  .highlight {
    color: var(--highlight-color);
    font-weight: bold;
  }

  .interactive-button {
    background: linear-gradient(90deg, var(--primary-color), var(--accent-color));
    border: none;
    color: white;
    padding: 12px 24px;
    text-align: center;
    text-decoration: none;
    display: inline-block;
    font-size: 16px;
    border-radius: 8px;
    transition: transform 0.2s, box-shadow 0.2s;
    margin: 10px 0;
    cursor: pointer;
  }

  .interactive-button:hover {
    transform: translateY(-3px);
    box-shadow: 0 4px 15px rgba(0, 0, 0, 0.3);
  }

  .notification {
    position: fixed;
    bottom: 20px;
    right: 20px;
    background: var(--secondary-color);
    padding: 15px;
    border-radius: 8px;
    box-shadow: 0 4px 8px rgba(0,0,0,0.2);
    animation: fadeIn 0.5s ease-in-out;
    backdrop-filter: blur(5px);
    border: 1px solid rgba(255,255,255,0.2);
  }

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

  .floating-label {
    position: absolute;
    top: 20px;
    right: 20px;
    background: rgba(255,255,255,0.2);
    padding: 5px 10px;
    border-radius: 20px;
    font-size: 0.8rem;
    backdrop-filter: blur(5px);
    color: white;
  }

  .section-divider {
    height: 2px;
    background: linear-gradient(90deg, transparent, var(--primary-color), transparent);
    margin: 40px 0;
    border: none;
  }

  @media (max-width: 768px) {
    .grid-container {
      grid-template-columns: 1fr;
    }

    h1 {
      font-size: 2rem;
    }

    h2 {
      font-size: 1.5rem;
    }

    h3 {
      font-size: 1.3rem;
    }

    .glass-card {
      padding: 20px;
    }
  }

  .demo-notice {
    position: fixed;
    top: 20px;
    left: 50%;
    transform: translateX(-50%);
    background: rgba(255,255,255,0.9);
    padding: 10px 20px;
    border-radius: 30px;
    box-shadow: 0 4px 15px rgba(0,0,0,0.1);
    z-index: 1000;
    backdrop-filter: blur(5px);
    border: 1px solid rgba(255,255,255,0.3);
    font-size: 0.9rem;
    color: var(--primary-color);
  }