or="emailSubjectTemplate">Email Subject Template</label>
                                    <input type="text" id="emailSubjectTemplate" name="emailSubjectTemplate" class="form-control" 
                                           placeholder="Invoice {invoice_number} from {company_name}">
                                    <small class="form-text text-muted">
                                        Variables: {invoice_number}, {company_name}, {customer_name}, {total_amount}
                               