jquery移除属性值

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
 <head>
  <title></title>
  <meta http-equiv="Content-Type" content="text/html;charset=UTF-8" />
  <style type="text/css"> 
  </style>
  <script  type="text/javascript" src="jquery-1.7.1.min.js"></script>
  <script type="text/javascript">
        window.onload=function(){
            $('#btnOk').click(function(){
            //移除属性值（把font元素下的color属性移除）    
                $('font').removeAttr('color');
            });
        };
  </script>
 </head>
 <body>
    <font color='#336699'>字体10</font>
    <hr />
    <font>字体2</font>
    <hr />
  <input type="button" id='btnOk' value='确定'  />
 </body>
</html>