(function(c){function d(a){a=a.replace(/left|top/g,"0px");a=a.replace(/right|bottom/g,"100%");a=a.replace(/([0-9\.]+)(\s|\)|$)/g,"$1px$2");var b=a.match(/(-?[0-9\.]+)(px|\%|em|pt)\s(-?[0-9\.]+)(px|\%|em|pt)/);return[parseFloat(b[1],10),b[2],parseFloat(b[3],10),b[4]]}c.extend(c.fx.step,{backgroundPosition:function(g){if(!g.bgPosReady){var a=c.curCSS(g.elem,"backgroundPosition");if(!a){return false}a=d(a);g.start=[a[0],a[2]];var h=d(g.end);g.end=[h[0],h[2]];g.unit=[h[1],h[3]];g.bgPosReady=true}var b=[];b[0]=((g.end[0]-g.start[0])*g.pos)+g.start[0]+g.unit[0];b[1]=((g.end[1]-g.start[1])*g.pos)+g.start[1]+g.unit[1];g.elem.style.backgroundPosition=b[0]+" "+b[1]}})})(jQuery);