css outline 在元素周围画线

编辑代码

<!DOCTYPE html>
<html>
<head>
<style>
p{
  border:1px solid red;
  outline:green dotted thick;
}
</style>
</head>

<body>
<p><b>Note:</b> IE8 supports the outline properties only if a !DOCTYPE is 
specified.</p>
</body>
</html>