if(document.layers){ // If Netscape 4
layerRef='document.'
topRef='.top'
leftRef='.left'
}else {//if(document.all){ // If IE4
layerRef=''
topRef='.style.pixelTop'
leftRef='.style.pixelLeft'
}

function moveLayer(layer,xstop,ystop,step,speed){
var go;

if(eval(layerRef+layer+leftRef)>xstop){
go=true
eval(layerRef+layer+leftRef+'-='+step)
}
if(eval(layerRef+layer+topRef)<ystop){
go=true
eval(layerRef+layer+topRef+'+='+step)
}
if(go){
setTimeout("moveLayer('"+layer+"',"+xstop+","+ystop+","+step+","+speed+")",speed)
}
if(!go) moveBack('divDuck', 625, 100,2,5)

}

function moveBack(layer,xstop,ystop,step,speed){
var go;
if(eval(layerRef+layer+leftRef)<xstop){
go=true
eval(layerRef+layer+leftRef+'+='+step)
}
if(eval(layerRef+layer+topRef)>ystop){
go=true
eval(layerRef+layer+topRef+'-='+step)
}
if(go){
setTimeout("moveBack('"+layer+"',"+xstop+","+ystop+","+step+","+speed+")",speed)
}

}


var windowWidth, windowHeight;
 

/*
 if (window.innerWidth) {
  winW = window.innerWidth;
  winH = window.innerHeight;
 }

 if (document.body.offsetWidth > 0) 
  winW = document.body.offsetWidth;
  winH = document.body.offsetHeight;
 }

*/	


function moveDuck()
{
	windowWidth = document.body.offsetWidth;
	windowHeight = document.body.offsetHeight;
	divDuck.style.pixelTop = 100;
	divDuck.style.pixelLeft = 625;	
	moveLayer('divDuck', 0,windowHeight - 100,2,5);
}

moveDuck();