/*var speed=30
demo2.innerHTML=demo1.innerHTML
function Marquee(){
if(demo2.offsetWidth-demo.scrollLeft<=0)
demo.scrollLeft-=demo1.offsetWidth
else{
demo.scrollLeft++
}
}
var MyMar=setInterval(Marquee,speed)
demo.onmouseover=function() {clearInterval(MyMar)}
demo.onmouseout=function() {MyMar=setInterval(Marquee,speed)}
*/
var dir=1//每步移动像素，大＝快
var speed=15//循环周期（毫秒）大＝慢
demo2.innerHTML=demo1.innerHTML
function Marquee(){//正常移动
        //alert(demo2.offsetWidth+"\n"+demo.scrollLeft)
        if (dir>0  && (demo2.offsetWidth-demo.scrollLeft)<=0) demo.scrollLeft=0
        if (dir<0 &&(demo.scrollLeft<=0)) demo.scrollLeft=demo2.offsetWidth
        demo.scrollLeft+=dir
        
        demo.onmouseover=function() {clearInterval(MyMar)}//暂停移动
        demo.onmouseout=function() {MyMar=setInterval(Marquee,speed)}//继续移动
}
function r_left(){if (dir=-1)dir=1}//换向左移
function r_right(){if (dir=1)dir=-1}//换向右移

var MyMar=setInterval(Marquee,speed)