body { background-color: #f8f9fa; font-family: 'Segoe UI', sans-serif; }
        .sidebar {
            position: fixed; top: 0; left: 0; width: 250px; height: 100%;
            background-color: #343a40; color: white; padding: 20px;
        }
        .sidebar .nav-link { color: #f8f9fa; margin-bottom: 10px; }
        .sidebar .nav-link:hover { background-color: #495057; border-radius: 5px; }
        .content { margin-left: 250px; padding: 30px; }
        .stat-card {
            border-radius: 1rem; padding: 2rem; text-align: center;
            box-shadow: 0 0.5rem 1rem rgba(0,0,0,0.1); color: white;
        }
        .stat-number { font-size: 2.5rem; font-weight: bold; }
        .bg-apartment { background-color: #007bff; }
        .bg-house { background-color: #28a745; }
        .bg-tenant { background-color: #dc3545; }
        .bg-paid { background-color: #198754; }
        .bg-unpaid { background-color: #ffc107; color: black; }

        @media (max-width: 768px) {
            .sidebar { width: 100%; position: relative; }
            .content { margin-left: 0; }
        }
        .features-btn {
    animation: pulse 2s infinite;
    transition: transform 0.2s ease-in-out;
  }

  .features-btn:hover {
    transform: scale(1.05);
  }

  @keyframes pulse {
    0% { box-shadow: 0 0 0 0 rgba(13, 110, 253, 0.6); }
    70% { box-shadow: 0 0 0 10px rgba(13, 110, 253, 0); }
    100% { box-shadow: 0 0 0 0 rgba(13, 110, 253, 0); }
  }