How to remove the border outline around the radio button?

It seems you are trying to remove the box shadow around the radio button. Is that correct? 

Please inject the following custom css code in form to remove the back shadow:

.form-line-error input:not(#coupon-input), .form-line-error .form-validation-error

{

    box-shadow: none !important;

}

The following guide should help you how to inject custom css code in form:   https://www.jotform.com/help/117-How-to-Inject-Custom-CSS-Codes 

Hope this helps.

Do get back to us if you have any questions.