fitting page to different screens

this is my first run at setting up anything remotely like this so please excuse me if I come off as a complete idiot. I am running the 2014 theme. when I am on the desktop version there is a small gray bar that run the length of the page on the right side. I am trying to figure out how to expand the page so that this bar no longer shows. https://www.shootintheskeet.com is the site. any help is appreciated. thanks guys.