第20行有个“ד，请问问题出在哪？
<!DOCTYPE HTML>
<html>
<heda>
<meta http-equiv="content-type" content="text/html; charset=utf-8">
<title>浮动1、2、3</title>
<style type="text/css">
div{
width:200px;
height:200px;
border:2px solid green;
float:left;
text-align:center;
font-size:30px;
color:blue;
margin:30px;
}
</style>
</heda>
<body>
<div id="div1">框架1</div>
<div id="div2">框架2</div>
<div id="div3">框架2</div>
</body>
</html>
