:root {
    --primary: #0f2027;
    --secondary: #203a43;
    --accent: #2c5364;
    --highlight: #4caf50;
    --text: #ffffff;
    --card-bg: #1e2a38;
    --btn-primary: #ff9800;
    --btn-hover: #ffa726;
    --btn-active: #fb8c00;
    --chart-color: #2196f3;
    --loader-color: #3498db;
    --font-main: 'Roboto', sans-serif;
  }

  @import url('https://fonts.googleapis.com/css2?family=Roboto:wght@300;400;500;700&display=swap');

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

  body {
    font-family: var(--font-main);
    color: var(--text);
    background: linear-gradient(135deg, var(--primary), var(--secondary), var(--accent));
    line-height: 1.6;
    overflow-x: hidden;
    position: relative;
    min-height: 100%;
    padding-bottom: 50px;
  }

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

  header {
    padding: 30px 0;
    text-align: center;
    position: relative;
    z-index: 10;
  }

  .header-content {
    background: rgba(30, 42, 56, 0.8);
    padding: 30px;
    border-radius: 15px;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.3);
    backdrop-filter: blur(10px);
    border: 1px solid rgba(255, 255, 255, 0.1);
  }

  h1, h2, h3, h4 {
    font-weight: 500;
    margin-bottom: 20px;
    line-height: 1.3;
  }

  h1 {
    font-size: 2.5rem;
    background: linear-gradient(90deg, #4facfe 0%, #00f2fe 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    margin-bottom: 15px;
  }

  h2 {
    font-size: 1.9rem;
    color: #4facfe;
    margin-top: 40px;
    padding-bottom: 10px;
    border-bottom: 2px solid rgba(79, 172, 254, 0.3);
  }

  h3 {
    font-size: 1.6rem;
    color: #00f2fe;
    margin-top: 30px;
  }

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

  .notice {
    background: rgba(255, 152, 0, 0.1);
    border-left: 4px solid var(--btn-primary);
    padding: 15px;
    margin: 30px 0;
    border-radius: 0 5px 5px 0;
    font-size: 1rem;
  }

  /* Article styling */
  article {
    background: rgba(30, 42, 56, 0.6);
    padding: 40px;
    border-radius: 15px;
    margin: 40px 0;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.2);
    position: relative;
    overflow: hidden;
  }

  article::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: radial-gradient(circle at 20% 50%, rgba(79, 172, 254, 0.1) 0%, transparent 50%);
    z-index: -1;
  }

  /* Code blocks */
  pre {
    background: #1a2635;
    border-radius: 8px;
    padding: 20px;
    margin: 25px 0;
    overflow: auto;
    box-shadow: inset 0 0 10px rgba(0, 0, 0, 0.5);
    border-left: 4px solid var(--highlight);
    position: relative;
  }

  pre::before {
    content: 'CSS';
    position: absolute;
    top: 0;
    left: 0;
    background: var(--highlight);
    color: white;
    padding: 2px 10px;
    font-size: 0.8rem;
    border-bottom-right-radius: 5px;
  }

  code {
    font-family: 'Courier New', monospace;
    color: #e1e1e1;
    font-size: 0.95rem;
    line-height: 1.5;
  }

  /* Images */
  .image-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
    gap: 20px;
    margin: 30px 0;
  }

  .image-card {
    background: var(--card-bg);
    border-radius: 10px;
    overflow: hidden;
    box-shadow: 0 5px 15px rgba(0, 0, 0, 0.2);
    transition: transform 0.3s ease, box-shadow 0.3s ease;
  }

  .image-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 10px 25px rgba(0, 0, 0, 0.3);
  }

  .image-card img {
    width: 100%;
    height: auto;
    display: block;
    border-bottom: 1px solid rgba(255, 255, 255, 0.1);
  }

  .image-caption {
    padding: 15px;
    font-size: 0.9rem;
    color: rgba(255, 255, 255, 0.7);
  }

  /* Buttons */
  .btn {
    display: inline-block;
    background-color: var(--btn-primary);
    color: white;
    padding: 12px 25px;
    border: none;
    border-radius: 5px;
    font-size: 1rem;
    font-weight: 500;
    text-decoration: none;
    cursor: pointer;
    transition: all 0.3s ease;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
  }

  .btn:hover {
    background-color: var(--btn-hover);
    transform: translateY(-2px);
    box-shadow: 0 6px 12px rgba(0, 0, 0, 0.15);
  }

  .btn:active {
    background-color: var(--btn-active);
    transform: translateY(0);
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
  }

  /* Cards */
  .card {
    background: var(--card-bg);
    border-radius: 10px;
    padding: 25px;
    margin: 20px 0;
    box-shadow: 0 5px 15px rgba(0, 0, 0, 0.2);
    border: 1px solid rgba(255, 255, 255, 0.1);
    transition: transform 0.3s ease, box-shadow 0.3s ease;
  }

  .card:hover {
    transform: translateY(-5px);
    box-shadow: 0 10px 25px rgba(0, 0, 0, 0.3);
  }

  /* Navigation */
  .nav-container {
    position: sticky;
    top: 0;
    z-index: 100;
    background: rgba(15, 32, 39, 0.9);
    backdrop-filter: blur(10px);
    padding: 15px 0;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.2);
  }

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

  .nav-links {
    display: flex;
    gap: 25px;
  }

  .nav-links a {
    color: var(--text);
    text-decoration: none;
    font-weight: 500;
    font-size: 1rem;
    transition: color 0.3s ease;
    position: relative;
  }

  .nav-links a:hover {
    color: #4facfe;
  }

  .nav-links a::after {
    content: '';
    position: absolute;
    bottom: -5px;
    left: 0;
    width: 0;
    height: 2px;
    background: #4facfe;
    transition: width 0.3s ease;
  }

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

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

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

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

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

  /* Responsive */
  @media (max-width: 768px) {
    .container {
      padding: 0 15px;
    }

    article {
      padding: 25px;
    }

    h1 {
      font-size: 2rem;
    }

    h2 {
      font-size: 1.6rem;
    }

    h3 {
      font-size: 1.3rem;
    }

    .nav-links {
      gap: 15px;
    }

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

  @media (max-width: 480px) {
    .header-content {
      padding: 20px;
    }

    article {
      padding: 20px 15px;
    }

    pre {
      padding: 15px;
    }

    .nav-container {
      padding: 10px 0;
    }

    nav {
      flex-direction: column;
      gap: 10px;
    }

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

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

  .particle {
    position: absolute;
    background: rgba(255, 255, 255, 0.5);
    border-radius: 50%;
    animation: float 10s infinite ease-in-out;
  }

  @keyframes particles {
    0% { transform: translateY(0) rotate(0deg); }
    100% { transform: translateY(-1000px) rotate(720deg); }
  }

  /* Footer */
  footer {
    text-align: center;
    padding: 20px;
    background: rgba(15, 32, 39, 0.8);
    margin-top: 50px;
    font-size: 0.9rem;
    color: rgba(255, 255, 255, 0.7);
  }

  /* Scroll indicator */
  .scroll-indicator {
    position: fixed;
    bottom: 20px;
    right: 20px;
    width: 50px;
    height: 50px;
    background: rgba(79, 172, 254, 0.2);
    border-radius: 50%;
    display: flex;
    justify-content: center;
    align-items: center;
    cursor: pointer;
    transition: all 0.3s ease;
    z-index: 99;
  }

  .scroll-indicator:hover {
    background: rgba(79, 172, 254, 0.4);
  }

  .scroll-indicator i {
    color: #4facfe;
    font-size: 1.5rem;
  }