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!

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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/

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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.