JS 实现文字左右滚动，必不可少的样式

<div >
             var speded=30
             dvvv2.innerHTML=dvvv1.innerHTML
             function Marqpuee(){
             if(dvvv2.offsetWidth-dvvv.scrollLeft<=0)
             dvvv.scrollLeft-=dvvv1.offsetWidth
             else{
             dvvv.scrollLeft++
             }
             }
             var MyMmar=setInterval(Marqpuee,speded)
             dvvv.onmouseover=function() {clearInterval(MyMmar)}
             dvvv.onmouseout=function() {MyMmar=setInterval(Marqpuee,speded)}
        </script>