Javascript?/CSS - Drop Down Menu

I wa开发者_如何学JAVAs looking for some kind of code similar to Gmail's Chat on Gmail's Page: a drop-down menu that pushes everything else that is down to the chat, but for some reason I couldn't see the page's source and I haven't found the same code in any other page. Does anybody know some page with similar code?

Regards!

You can use jQuery's native slideDown function to show hidden elements that will push content down below them, depending on your slideDown element's CSS positioning and float.

http://api.jquery.com/slideDown/

You can have a which height is set to 0px or auto to make it expand/collapse.

You can also give a sliding effect by gradually increasing/decreasing the height of the div.

As long as it's not positioned absolute, it will push the content below.