app/assets/javascripts/login.js
$(document).ready(function(){
$(document).mousemove(function(e){
TweenLite.to($('body'),
.5,
{ css:
{
backgroundPosition: ""+ parseInt(event.pageX/8) + "px "+parseInt(event.pageY/'12')+"px, "+parseInt(event.pageX/'15')+"px "+parseInt(event.pageY/'15')+"px, "+parseInt(event.pageX/'30')+"px "+parseInt(event.pageY/'30')+"px"
}
});
});
});