Scrollbar not shown, but space still exists

[BeerBelly]

If you can check this webpage: http://wasup.si/test-bfcid1 you can see what I mean.
I moved the sidebar to the right, but I can't seem to get the page to fill the whole space without the scrollbar area....can you help with this?

[makotot]

I cannot access the url. Basic auth is required.