Window size

Rails
1

I hope someone could help me on my problem.
I want to show my div(User Add Form) at center of the browser
window.like pop up window.the Pop-Up has to be shown at center of the
browser’s window
I used this code.In FireFox 3.
element.style.top = ( 0 + ( window.innerHeight )/2 - ( dimensions.height
)/2 ) + ‘px’;
element.style.left = ( window.innerWidth )/2 - ( dimensions.width )/2 +
‘px’;
but it was not positioned center.
Pls help me up.

2

This is not a rails question. Please ask it elsewhere.

Ryan B.
Freelancer