ATAHUALPA adjustment

Hello

I am tweaking a new blog element to an existing site. The theme is Atahualpa and i have changed the Logo to be a big banner at the top of the page ( http://www.pogofilms.com/wordpressblog/ ) – however, as you can see if you go between that page and anyother page of pogofilms.com , there is a thin white line at the top of the site which i would like to get rid of.

Any suggestions?

Thanks!

Phil