how to achieve the effect of the center post scrolling up out of the bottom of screen
 

Hi!

I was wondering if it is possible to get the center post of the theme to act like this:
http://www.ringvemedia.com/beijing-blog

see how the posts kind of just scroll up out of the bottom, while the background remains fixed?
I know how to make the bg fixed, I just want to know how I can achieve the effect of the center content scrolling up out of the bottom of the screen.

thank you!

EDIT:

another question... how can i get a static bar across the screen like that? see how it overlays the center post and doesn't move? is there a plugin for this?

or if i can't have a horizontal bar like that, is there someway, i can make a side bar static? so that the menu i place in it doesn't move up and down like the blog post.

add the following to ATO->Body, Text & Links->Body Style