How to upload modified Source Code to my form?

I read in the Forum that you can download a form's source code to modify it outside of Form Builder. However, I don't see how we upload the modified code back to the form? I wanted to edit some custom code and see if that resolves my alignment problems that I haven't been able to fix by simply adding CSS within the Form Builder. Can this be done? If so, how?

Thanks!

You can not actually, you can only use that modified code to embed your form in an website for example, but you can not upload the code back to the form. The only adjustments that could be done are with Custom CSS.

If you have any problems with your form, please  let us know the details and we will check for you.

Thank you!