Breakaway button even in responsive mode

1- Responsive mode

I check the responsive mode and when I test my site in another devices, the send botton smash:

http://198.46.81.209/~cappta5/

I was able to replicate mentioned issue on your embedded form and also on your standalone form. You can make your submit button responsive by Injecting Custom CSS. Inside of your Form Builder select Setup & Embed tab, then click on Preferences, then select Form Styles tab and inside of Inject Custom CSS field at the bottom of existing code paste this code:

.form-submit-button {

    width : 100%!important;

}

After you add this code your form should look like this. 

Here is my cloned form where I added mentioned CSS code: https://form.jotform.com/60454796774975 

Feel free to clone it. 

Hope this will help. Let us know if you need further assistance.