CSS change div bg when finger is on it (ipad)

Question

#numpad table td#key1 {
  background-image: url("1.png");
}
#numpad table td#key1:active,
#numpad table td#key1:focus {
  background-image: url("1d.png");
}

this works like i want it to on the computer (the image changes when i push my mouse key down on it), but it has no effect on the ipad. how can i do this on ipad so that when my finger is on one of the images it will change it with css?

Answer 1

I doubt you can do that using pure CSS on a touch device.

Here are some Javascript based answers.