JS实现文字向上无缝滚动效果

<!doctype html>
<html lang="en">
  <head>
    <meta http-equiv="Content-Type" content="text/html; charset=utf-8" />      
    <meta name="keywords" content="关键字1,关键字2" />    
    <meta name="Description" content="描述信息" />
    <title>循环滚动</title>
    <!--CSS/JS-->
    <style type="text/css">
      *{margin:0;padding:0;}
      ul,li{list-style:none;display:block;}
      #scrollBox{height:150px;width:300px;margin:100px auto;background:#f09;overflow:hidden;}
      #scrollBox #con1,#con2{width:280px;float:left;}
      #scrollBox li{height:15px;line-height:15px;text-align:center;}

    </style>

  </head>
 <body>
    <!--div-->
  <div id="scrollBox">
    <ul id="con1">
      <li>李华 中了10块钱<li>
      <li>Leo 中了一个手机<li>
      <li>刘明 中了一块毛巾<li>
      <li>ll 中了保温杯<li>
      <li>nice 中了100块钱红包<li>
      <li>108 中了20元优惠券<li>
      <li>ok 中了100块钱<li>
      </ul>
    <ul id="con2"></ul>
  </div>
  <script type="text/javascript">      
        var area =document.getElementById('scrollBox');
        var con1 = document.getElementById('con1');
        var con2 = document.getElementById('con2');
        con2.innerHTML=con1.innerHTML;
        function scrollUp(){
        if(area.scrollTop>=con1.offsetHeight){
          area.scrollTop=0;
        }else{
          area.scrollTop++
        }
        }        
        var time = 50;
        var mytimer=setInterval(scrollUp,time);
        area.οnmοuseοver=function(){
          clearInterval(mytimer);
        }
        area.οnmοuseοut=function(){
          mytimer=setInterval(scrollUp,time);
        }
    </script>
 </body>

</html>