// JavaScript Document
  function product_roll(){
      var speed=10; //数字越大速度越慢
      var tab=document.getElementById("demo");
      var tab1=document.getElementById("demo1");
      var tab2=document.getElementById("demo2");
      tab2.innerHTML=tab1.innerHTML;
      function Marquee(){
      if(tab2.offsetWidth-tab.scrollLeft<=0)
      tab.scrollLeft-=tab1.offsetWidth
      else{
      tab.scrollLeft++;
      }
      }
      var MyMar=setInterval(Marquee,speed);
      tab.onmouseover=function() {clearInterval(MyMar)};
      tab.onmouseout=function() {MyMar=setInterval(Marquee,speed)};
	  }
	function setTab12(name,cursel,n){
	for(i=1;i<=n;i++){
	var menu=document.getElementById(name+i);
	var con=document.getElementById(name+"_"+i);
	//menu.checked=i==cursel?"true":"";
	menu.className = i== cursel?"news_bc":"news_bc1";
	con.style.display=i==cursel?"block":"none";
	}
	}