Make the background clickable for advertisement (sides next to container)
 

I want to make the background clickable for advertisement. You can see below what I mean:
http://s19.postimage.org/xiy592fmr/clickable_area.jpg

So I upload a new background and if a visitor clicks on the sides of the page, he goes to the site of the advertiser. You see a lot of sites with this function, but I don't know how to do it with Atahualpa 3. You can see it on this site: http://www.pokernews.com/

The site you pointed to doesn't have any clickable areas outside the main content.