var bgx=0;
/*document.write('<p id="bgx">'+bgx+'</p>');*/
movebg();

function movebg(){
 bgx--;
 if (bgx <= -600) bgx=0;
 /*document.getElementById('bgx').innerHTML+=bgx;*/
 document.body.style.backgroundPosition=bgx+"px bottom";
 setTimeout('movebg()', 100);
}