class="modal-body">
                <form id="testEmailForm">
                    <div class="form-group">
                        <label for="testEmailAddress">Send test email to:</label>
                        <input type="email" id="testEmailAddress" class="form-control" required 
                               placeholder="test@example.com">
                    </div>
                    <div class="form-group">
                        <label for="testInvoiceId">Use invoice for testing:</label>
       