How does twitter flip reading panel\

I need to flip a div panel left once a some item div get clicked and hide,once item div get clicked again. (exactly like new twitter reading panel) i have tried several methods but i couldn't animate it smooth.
recently i identified it not happen smoothly because of the bad what i did.i increased width of outter div and decrese width of outter div. are there any good suggestion or code snippet to work my need??
Here is the code that i have used for animate and gt show the more read div panel

$("#more-item").animate({"width": "toggle"}, { duration: 500,specialEasing: {width: 'linear', height: 'easeOutBounce'} });

Code (markup):

Here is the scenario that i need to see.

1. clicked on item div
2. more read div panel animate and flip to left and show the content
3. click again item div
4. more read div panel animate and flip right and hide

when we at third point if we again click another item div just load content of recent clicked div instead animate and hide the more read div

here is the screen shot what my need functioning on new twitter reading panel.


thanks