body {
      font-family: 'Segoe UI', sans-serif;
      margin: 0;
      background-color: #f8fafc;
      color: #111827;
      transition: background-color 0.4s, color 0.4s;
    }

    header {
      background-color: #1e3a8a;
      color: white;
      padding: 1rem;
      display: flex;
      justify-content: space-between;
      align-items: center;
      flex-wrap: wrap;
    }

    .title {
      font-size: 1.5rem;
    }

    nav ul {
      display: flex;
      list-style: none;
      gap: 1rem;
      padding: 0;
      margin: 0;
      flex-wrap: wrap;
    }

    nav a, button {
      color: white;
      text-decoration: none;
      padding: 0.5rem 0.75rem;
      background-color: transparent;
      border: none;
      cursor: pointer;
      transition: background-color 0.3s;
    }

    nav a:hover, button:hover {
      background-color: #3b82f6;
      border-radius: 6px;
    }

    main {
      padding: 2rem;
      display: grid;
      grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
      gap: 1.5rem;
    }

    .card {
      background: white;
      padding: 1rem 1.5rem;
      border-radius: 12px;
      box-shadow: 0 4px 8px rgba(0,0,0,0.1);
      transition: transform 0.3s ease;
    }

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

    .tabs {
      display: flex;
      gap: 1rem;
      margin-top: 1rem;
    }

    .tabs button {
      padding: 0.5rem 1rem;
      border: none;
      background: #e5e7eb;
      border-radius: 8px;
      cursor: pointer;
      transition: background 0.3s;
    }

    .tabs button.active {
      background: #2563eb;
      color: white;
    }

    .modal {
      display: none;
      position: fixed;
      top: 0; left: 0;
      width: 100vw;
      height: 100vh;
      background: rgba(0,0,0,0.6);
      justify-content: center;
      align-items: center;
      z-index: 1000;
    }

    .modal-content {
      background: white;
      padding: 2rem;
      border-radius: 12px;
      max-width: 400px;
      width: 100%;
    }

    canvas {
      width: 100% !important;
      height: 300px !important;
    }

    .spinner {
      border: 4px solid rgba(0,0,0,0.1);
      border-radius: 50%;
      border-top: 4px solid #2563eb;
      width: 40px;
      height: 40px;
      animation: spin 1s linear infinite;
    }

      .page {
      animation: fadeIn 0.5s ease-in-out;
      }
      
    .notification {
      position: fixed;
      top: 20px;
      right: 20px;
      background: #38bdf8;
      color: white;
      padding: 1rem 1.5rem;
      border-radius: 10px;
      box-shadow: 0 0 10px rgba(0,0,0,0.2);
      z-index: 9999;
      opacity: 0;
      pointer-events: none;
      transform: translateY(-20px);
      transition: all 0.3s ease;
    }
    .notification.show {
      opacity: 1;
      pointer-events: auto;
      transform: translateY(0);
    }
    @keyframes fadeIn {
      from { opacity: 0; transform: translateY(10px); }
      to { opacity: 1; transform: translateY(0); }
    }
    @media (max-width: 480px) {
      header h1 { font-size: 1.2rem; }
      nav ul { flex-direction: column; }
      .card { padding: 1rem; }
      canvas { height: 200px !important; }
    }

    @media (max-width: 600px) {
      nav ul {
        flex-direction: column;
        align-items: flex-start;
      }
    }