// JavaScript Document
function scrollImg(){
	//alert();
    var posX,posY;
    if (window.innerHeight) {
        posX = window.pageXOffset;
        posY = window.pageYOffset;
    }
    else if (document.documentElement && document.documentElement.scrollTop) {
        posX = document.documentElement.scrollLeft;
        posY = document.documentElement.scrollTop;
    }
    else if (document.body) {
        posX = document.body.scrollLeft;
        posY = document.body.scrollTop;
    }
    var ad=document.getElementById("lefts");
		//alert(document.getElementById("infott"));

	//document.getElementById("infott").innerHTML=(posY);//测试
   ad.style.top=(posY+368)+"px";
   // ad.style.bottom=(posY)+"px";
    ad.style.right="0px";
	//ad.innerHTML ="此广告位招租" +  document.body.scrollTop
    setTimeout("scrollImg()",50);
}
scrollImg();