function slide(){
	var posY1=parseInt(document.getElementById("cbd").offsetTop);
	var posY2=document.documentElement.scrollTop+50;
	var Yoffset=(posY2-posY1);
	
	if(Math.abs(Yoffset)>0){
		document.getElementById("cbd").style.top = parseInt(document.getElementById("cbd").offsetTop)+(Yoffset/20)+"px";
	}
	setTimeout("slide()",10);
}

onload=slide;