edit error message in the form field

Is there a way to remove the 'red box' as my client going through the form? I want to have the error message be at the end or above the form once they try to submit - where it says, 'please fill out all required fields' not as they go along completing the form.

I have checked your form and you have removed the error message box.

To clarify, do you wan to change the red border created when there is an empty field?

You can add this custom CSS to replace the red border color

li.form-line-error input:not(#coupon-input), li.form-line-error select, li.form-line-error textarea, li.form-line-error .form-validation-error {
   

border: 1px solid black !important;
  
}

You can adjust the color of the border.

Guide:https://www.jotform.com/help/117-How-to-Inject-Custom-CSS-Codes

If you need further assistance, let us know.