Need Tiled Gallery to be full width

Hi I am using WP Visual Bakery and want to use the Jetpack tiled gallery. The problem is that my gallery shows only have of the page. I need it to be the same size as the rest of my site. I don’t want to change my functions.php because I don’t feel comfortable doing it. Do you have CSS to change it? I’ve tried but couldn’t get it to work. Any other way?