Possible fix for demo number issues in Safari.

Hi Lea,

Thanks for your great site with animation examples.

In Safari (5.1 on W7) I noticed that the demo numbers decrement when hovering over certain demo tiles (e.g. demo 9). 

I found a solution/workaround: by moving the counter-increment to the :before pseudo element, the demo counter behaves OK in Safari.

I hope this helps.