I\'m trying to change img src (not the background img src) with css
#btnUp{
cursor:poi
You can use a mixture of JavaScript and CSS to achieve this, but you can not do this with CSS alone.
Instead of img you would put file name sans file type.
function change(img){
document.getElementById("btnUp").src= img + ".png";
}
function changeback(img){
document.getElementById("btnUp").src= img + ".png";
}
Then you use CSS to modify the img tag or the id to your liking.