twentyeleven dynamic page height

I know how to change the “page” height to a static height with “height: 1000px;”

I’m looking for a dynamic full “page” height instead of static.

I got my sidebar to go full height with “height: 100%;” or “min-height: 100%;”

But can’t get the “page” to do the same.

I did get it to work if I change the “page” height to something crazy like 1000px or something, but I don’t like over-shooting it to make it look right if I can do it dynamically.

FYI: I’m not concerned about the footer disappearing as I am going to make the footer static also.

Any other suggestions?

https://upstairsroom.net/mercycares-design/404

Thanks