Why the full name field takes two rows for first and last name inputs

Problem no 4

Normally, when we add a Full Name field, the first and last name fields will appear next to each other. In that form, they appear one below the other. And I can't change their width setting. 

This is normal since the form appears to be styled with injected CSS. That CSS changes the field width to the responsive 100%.

We can try to check the CSS further if you really need to restore the default layout.