var speed3=30//速度数值越大速度越慢
    demopro2.innerHTML=demopro1.innerHTML
    function Marqueepro()
    {
     if(demopro2.offsetWidth-demopro.scrollLeft<=0)
      demopro.scrollLeft-=demopro1.offsetWidth
     else
      demopro.scrollLeft++
    } 
    var MyMarpro=setInterval(Marqueepro,speed3)
    demopro.onmouseover=function() {clearInterval(MyMarpro)}
    demopro.onmouseout=function() {MyMarpro=setInterval(Marqueepro,speed3)}