Form Builder - Css

Hi there, am using the latest version of cs cart and have created a basic contact form. I've noticed that there are some quirks with how the form is laid out - some of the fields don't line up and are squashed together. I guess I have to play with the css. Do I just go into the file editor area, css → add ons → form builder - > styles.css and play with css here? Is that the best way to do it? What will happen to that file when I upgrade? Thanks in advance.

“my changes”

Bless! Thanks : )