Comment section alignment

Hey Guys,
I’m so rusty with my CSS and my PHP knowledge isn’t the greatest. I have a website that I’m trying to edit the comment section on.

The site is: https://kirschelectricalcontracting.com/testimonials/

I need to add spacing between the comments/title and the boarder but I have no idea what part of the style.css it’s apart of! or if it’s a part of the comment.php

I’m using the Ifluid theme, let me know if you need any more info