body {
            background: linear-gradient(135deg, #f5f7fa 0%, #c3cfe2 100%);
        }
        
        .card {
            border: none;
            border-radius: 15px;
            overflow: hidden;
        }
        
        .card-header {
            border-bottom: none;
            padding: 20px;
        }
        
        .card-body {
            padding: 30px;
        }
        
        .form-control:focus {
            border-color: #252951;
            box-shadow: 0 0 0 0.2rem rgba(37, 41, 81, 0.25);
        }
        
        .btn:hover {
            transform: translateY(-2px);
            box-shadow: 0 4px 8px rgba(0, 0, 0, 0.2);
        }
        
        .input-group-text {
            border-right: none;
        }
        
        .form-control {
            border-left: none;
        }
        
        .form-control:focus + .input-group-text {
            border-color: #252951;
        }