:root {
    --primary: #1e3c72;
    --secondary: #2a5298;
    --accent: #39ff14;
    --text: #ffffff;
    --card-bg: rgba(255, 255, 255, 0.1);
    --nav-bg: rgba(0, 0, 0, 0.7);
    --sidebar-bg: rgba(30, 60, 114, 0.9);
  }

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

  body {
    background: linear-gradient(135deg, var(--primary), var(--secondary));
    color: var(--text);
    font-family: 'Roboto', sans-serif;
    line-height: 1.6;
    padding-top: 80px;
  }

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

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

  .header::after {
    content: '';
    display: block;
    width: 100px;
    height: 4px;
    background: var(--accent);
    margin: 20px auto;
    border-radius: 2px;
  }

  h1, h2, h3, h4 {
    font-weight: 700;
    margin-bottom: 20px;
  }

  h2 {
    font-size: 28px;
    color: var(--accent);
    position: relative;
    padding-bottom: 10px;
  }

  h2::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 50px;
    height: 2px;
    background: var(--accent);
  }

  h3 {
    font-size: 22px;
    margin-top: 30px;
  }

  p {
    margin-bottom: 20px;
    font-size: 16px;
  }

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

  .card {
    background: var(--card-bg);
    border-radius: 15px;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.2);
    padding: 25px;
    transition: all 0.3s ease;
    backdrop-filter: blur(10px);
    border: 1px solid rgba(255, 255, 255, 0.1);
  }

  .card:hover {
    transform: translateY(-10px);
    box-shadow: 0 15px 35px rgba(0, 0, 0, 0.3);
  }

  .card-img {
    width: 100%;
    height: 200px;
    object-fit: cover;
    border-radius: 10px;
    margin-bottom: 20px;
    box-shadow: 0 5px 15px rgba(0, 0, 0, 0.2);
    transition: transform 0.3s ease;
  }

  .card:hover .card-img {
    transform: scale(1.03);
  }

  .navbar {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    background: var(--nav-bg);
    padding: 15px 30px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    z-index: 1000;
    backdrop-filter: blur(10px);
  }

  .nav-links {
    display: flex;
    gap: 20px;
  }

  .nav-link {
    color: var(--text);
    text-decoration: none;
    font-weight: 500;
    position: relative;
    padding: 5px 0;
  }

  .nav-link::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--accent);
    transition: width 0.3s ease;
  }

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

  .sidebar {
    position: fixed;
    top: 80px;
    left: 0;
    width: 250px;
    height: calc(100vh - 80px);
    background: var(--sidebar-bg);
    padding: 30px 20px;
    box-shadow: 2px 0 10px rgba(0, 0, 0, 0.3);
    transform: translateX(-100%);
    transition: transform 0.3s ease;
    z-index: 999;
  }

  .sidebar.active {
    transform: translateX(0);
  }

  .sidebar-link {
    display: block;
    color: var(--text);
    text-decoration: none;
    padding: 10px 0;
    margin-bottom: 10px;
    border-bottom: 1px solid rgba(255, 255, 255, 0.1);
    transition: color 0.3s ease;
  }

  .sidebar-link:hover {
    color: var(--accent);
  }

  .menu-toggle {
    display: none;
    background: none;
    border: none;
    color: var(--text);
    font-size: 24px;
    cursor: pointer;
  }

  .button {
    display: inline-block;
    background: var(--accent);
    color: #000;
    border: none;
    padding: 12px 25px;
    border-radius: 5px;
    font-weight: 600;
    text-decoration: none;
    transition: all 0.3s ease;
    cursor: pointer;
    box-shadow: 0 4px 15px rgba(57, 255, 20, 0.3);
  }

  .button:hover {
    transform: scale(1.05);
    box-shadow: 0 6px 20px rgba(57, 255, 20, 0.4);
  }

  .card-flip {
    perspective: 1000px;
    height: 300px;
  }

  .card-inner {
    position: relative;
    width: 100%;
    height: 100%;
    transition: transform 0.6s;
    transform-style: preserve-3d;
  }

  .card-flip:hover .card-inner {
    transform: rotateY(180deg);
  }

  .card-front, .card-back {
    position: absolute;
    width: 100%;
    height: 100%;
    backface-visibility: hidden;
    border-radius: 15px;
    padding: 25px;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
  }

  .card-back {
    background: rgba(50, 50, 50, 0.9);
    transform: rotateY(180deg);
  }

  .chart {
    width: 100%;
    height: 300px;
    background: var(--card-bg);
    border-radius: 15px;
    position: relative;
    overflow: hidden;
    margin: 30px 0;
  }

  .chart::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.2), transparent);
    animation: moveGradient 3s linear infinite;
  }

  @keyframes moveGradient {
    0% { transform: translateX(-100%); }
    100% { transform: translateX(100%); }
  }

  pre {
    background: rgba(0, 0, 0, 0.3);
    border-radius: 10px;
    padding: 20px;
    margin: 20px 0;
    overflow-x: auto;
    border-left: 4px solid var(--accent);
  }

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

  .community {
    display: flex;
    flex-wrap: wrap;
    gap: 30px;
    padding: 40px 0;
  }

  .community-card {
    background: var(--card-bg);
    border-radius: 15px;
    padding: 25px;
    flex: 1 1 calc(33.333% - 30px);
    box-shadow: 0 5px 15px rgba(0, 0, 0, 0.2);
    transition: all 0.3s ease;
  }

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

  .reference {
    text-align: center;
    padding: 20px;
    background: rgba(0, 0, 0, 0.3);
    border-radius: 10px;
    margin: 40px 0;
    font-size: 14px;
    color: rgba(255, 255, 255, 0.7);
  }

  @media (max-width: 992px) {
    .sidebar {
      width: 200px;
    }
    
    .community-card {
      flex: 1 1 calc(50% - 30px);
    }
  }

  @media (max-width: 768px) {
    .navbar {
      padding: 15px 20px;
    }
    
    .sidebar {
      width: 250px;
    }
    
    .menu-toggle {
      display: block;
    }
    
    .nav-links {
      display: none;
    }
    
    .grid-container {
      grid-template-columns: 1fr;
    }
    
    .community-card {
      flex: 1 1 100%;
    }
  }

  @media (max-width: 576px) {
    body {
      padding-top: 70px;
    }
    
    h2 {
      font-size: 24px;
    }
    
    h3 {
      font-size: 20px;
    }
    
    .card {
      padding: 20px;
    }
  }