这样写应该是可以的吧？
<!DOCTYPE html>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>挑战题</title>
<script src="http://libs.baidu.com/jquery/1.9.0/jquery.js" type="text/javascript"></script>
<style type="text/css">
#jh{display: none;}
</style>
</head>
<body>
<ul>
<li></li>
<li></li>
<li></li>
<li></li>
<li><a href="#" onclick="djgd()"><span id="gd">更多</span></a><a href="#" onclick="djjh()"><span id="jh">简化</span></a></li>
</ul>
<script type="text/javascript">
function djgd(){
$('#gd').css('display','none');
$('#jh').css('display','block');
}
function djjh(){
$('#jh').css('display','none');
$('#gd').css('display','block');
}
</script>
</body>
</html>
