[jQuery] How to center a DIV using jQuery Component?

Hi there!
I'm developing a website with jQuery Component.
When I press any of the menu buttons the transition goes normally and
then the div stands right on top of the browser:
http://work.ricardomiguel.com/bailaogest/
My question is: how can I center vertically the different divs just
like the first link?
Can it be done with javaScript or is it a matter of CSS?
Thank you in advance.