$.fn.syncroll_b = function(){
			return this.each(function(){
			var o=$(this);
			var c=o.position();
			var thisPos=o.offset();
			var containerPos=o.offsetParent().offset();
			var scroller=$(window).scroll(function(){
				o.delayEfect(function(){
					return {
						top:Math.max(scroller.scrollTop() - containerPos.top + c.top ,c.top),
						left:Math.max(scroller.scrollLeft() - containerPos.left,c.left)
					}
				})
			})
		})
	}
	
	$.fn.delayEfect = function(paramGetter,cfg){
		var o=this;
		var c=$.extend((o.data('delayEfectCfg')||{
			delay:100,
			speed:300
		}),cfg);
		o.data('delayEfectCfg',c);
		if(c.timer)clearTimeout(c.timer);
		c.timer=setTimeout(function(){
			o.queue([]).animate(paramGetter(),c.speed);
		},c.delay)
	}
	$(window).load(function(){
		$('#go-top').syncroll_b()
	})