又哪有问题吗
<!DOCTYPE HTML>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>style样式</title>
</head>
<body>
<h2 id="con">I love JavaScript</h2>
<p> JavaScript使网页显示动态效果并实现与用户交互功能。</p>
<script type="text/javascript">
var mychar= document.getElementById("con");
mychar.style.color="red";
mychar.style.backgroundColor="blue";
mychar.style.width=200px;
</script>
</body>
</html>
为什么运行结果显示不出设置的效果，难道有又哪出问题了吗，求大佬指教
