CSS PAIRS - A game of memory and concentration

2 Player Game - Take it in turns to click 2 squares in the grid to reveal 2 numbers.
If the numbers match then leave them visible but click your score-card once to remember the score and have another free go.
If the pair of numbers doesn't match then click the numbers to turn them off and then let player 2 have their go.

The first one to get 13 pairs is the winner.

Not working in IE6 or Opera

Player 1

Player 2