White area on modular one-page

I started with grav last night and actually building a modular page. but when I view it I have a white area as you can see in the Screenshot. any ideas how to remove this? Screenshot_20160514-185517

this area is on mobile and desktop browsers.

We would need to be able to inspect the page directly to use browser web developer tools. Is this site reachable?

sorry I restarted my site. after I reused md files of an example I did not get this white area. but problem was there after following modular pages examples in the docs, so maybe I can reproduce it on my dev site