var speed=20
  demo2.innerhtml=demo1.innerhtml
 demo.scrollleft=demo.scrollwidth
  function marquee(){
  if(demo.scrollleft<=0)
  demo.scrollleft+=demo2.offsetwidth
  else{
  demo.scrollleft--
  }
  }
  var mymar=setinterval(marquee,speed)
  demo.onmouseover=function() {clearinterval(mymar)}
  demo.onmouseout=function() {mymar=setinterval(marquee,speed)}