function moveBackground(id){
  var obj = document.getElementById('navigation');
  var position = "0px " + ((id * 14) * -1) + "px"
  obj.style.background = "url(/images/navigation.gif) no-repeat " + position;
}

function resetBackground(){
  var obj = document.getElementById('navigation');
  obj.style.background = "url(/images/navigation.gif) no-repeat 0px 0px";
}