I checked your setup and the rows inside the section have the negative margins which is disturbing the layout (see screenshots)
Inspect your rows in Cornerstone and set the margins to 0. The other thing I noticed while checking your setup is that you've updated Cornerstone to the latest version but you haven't updated your Theme yet. This may cause future conflicts and potential errors. Please update your theme as well to avoid such conflicts. You can find the latest version numbers here: (http://theme.co/changelog/) Then you can compare them to what's installed on your site.
If you find anything to be out of date, you can review our update guide.