怎么不动?求大神指点
<body>
<div id="news">
<!--top-->
<div id="newstitle">最新课程<a href="#" target="_self">更多>></a></div>
<!--content-->
<div id="news-box">
<ul id="con1">
<li><a href="#">1.学会html5 绝对的屌丝逆袭(案例)</a><span>2013-09-18</span></li>
<li><a href="#">2.tab页面切换效果(案例)</a><span>2013-10-09</span></li>
<li><a href="#">3.圆角水晶按钮制作(案例)</a><span>2013-10-21</span></li>
<li><a href="#">4.HTML+CSS基础课程(系列)</a><span>2013-11-01</span></li>
<li><a href="#">5.分页页码制作(案例)</a><span>2013-11-06</span></li>
<li><a href="#">6.导航条菜单的制作(案例)</a><span>2013-11-08</span></li>
<li><a href="#">7.信息列表制作(案例)</a><span>2013-11-15</span></li>
<li><a href="#">8.下拉菜单制作(案例)</a><span>2013-11-22</span></li>
<li><a href="#">9.如何实现“新手引导”效果</a><span>2013-12-06</span></li>
</ul>
</div>
<!--bottom-->
<div id="news-boot"></div>
</div>
<script type="text/javascript">
var area=document.getElementById('news-box');
var con1=document.getElementById('con1');
area.innerHTML+=area.innerHTML;
area.scrollTop=0;
function scrollUp(){
if(area.scrollTop>=con1.offsetHeight){ area.scrollTop=0;}
else{area.scrollTop++;}
}
var time=50;
setInterval("scrollUp()",time);
</script>
</body>