HTML5: Animate page reflow?
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I am switching the contents of divs (fading old contents out, then fading new contents in) and because they are slightly different contents, the moment they change there is a jarring reorganization of everything below them. 

My question is, is there a way to make this movement smooth? 

I suspect that pretty much the only feasible way to do this is to use javascript to determine ahead of time what the heights (in my case I only deal with blocks where the vertical alignment shifts) of the starting and ending elements are, and assign these values directly. Once I do this I am sure CSS3 transition will apply a pleasant animation. 

Is there perhaps a way to get this without specifying explicit dimensions? I seem to recall at some point having experienced items getting moved around the page in an animated fashion. This gives me hope that it could be done using just CSS.