.bar:hover{
  -webkit-animation: myanim 5s infinite; /* Saf5, Chrome */
     -moz-animation: myanim 5s infinite; /* Firefox 5-15 */
       -o-animation: myanim 5s infinite; /* Opera 12+ */
          animation: myanim 5s infinite; /* Saf5, Chrome, Firefox 16+ */
}

@-webkit-keyframes myanim {
0%  {background:url(../img/bg.jpg) 0px 0;	
50%  {background:url(../img/bg.jpg) 100% 0;}
}
@-moz-keyframes myanim {
50%  { background:url(../img/footer-logo.png) no-repeat 90% 45%;}
}
@-o-keyframes myanim {
50%  { background:url(../img/footer-logo.png) no-repeat 90% 45%;}
}
@keyframes myanim {
50%  { background:url(../img/footer-logo.png) no-repeat 90% 45%;}
}