Adding horizontal padding on right of primary nav bar

Site URL: https://fpg.com

I'm running into an issue where I have several folders in my primary navigation bar, but when they drop down, they get cut off by the right side of the screen. I've included an image as shown, but am hoping to add some sort of padding on the far right side of the navigation screen. Id still like my links to be right aligned, because I know putting them in the center would technically solve my problem, but am hoping to just shift all of my content over a little to the left so that you're able to read whats in all the folders. Anyone know how to solve this problem?

Where is item in screenshot? I don't see on your site.