Web App | Div positioning

Hi

I am working on a iPad enhancement. I want a Div to remain on the bottom of the browser window, while other content to move on finger scroll. The LOC not working is:

$('div#myDocking').css({ 'position': 'absolute', 'top': $(window).height() - $('#myDocking').height() document.documentElement.scrollTop 'px' })

Please help resolving the issue.

Thanks!