Phone number field not displaying properly on the mobile devices

I am about to lose my mind!  I've read every response to this issue but none of the solutions are working on my form.  The Phone Number (Mobile Number on my form) field box is too small when displayed on mobile.  This happens on mobile preview and when viewed on an actual mobile device.  

Can some tell me IN DETAIL how to fix this problem?  I'm new to this so please explain as if I don't know anything! HAHA!

Here is my form:

https://form.jotform.com/91144385725157

Please try adding the following CSS code to the form to set the width of the phone number field on the mobile devices.

@media screen and (min-width: 10px) and (max-width: 540px){

#input_7_full {

   width: 335px !important;

}

}

Please get back to us if you need any further assistance. We will be happy to help.