$j.fn.center=function(options){var $w=$j(window),scrollTop=$w.scrollTop();return this.each(function(){var $this=$j(this),settings=$j.extend({against:'window',top:false,topPercentage:0.5},options),centerize=function(){var $against,x,y;if(settings.against==='window'){$against=$w;}else if(settings.against==='parent'){$against=$this.parent();scrollTop=0;}else{$against=$this.parents(against);scrollTop=0;}
x=(($against.width())-($this.outerWidth()))*0.5;y=(($against.height())-($this.outerHeight()))*settings.topPercentage+scrollTop;if(settings.top)y=settings.top+scrollTop;$this.css({'left':x,'top':y});};centerize();$w.resize(centerize);});};