<!DOCTYPE html>
<html>
<head>
<style type='text/css'>
.link_class {
width: 150px;
height: 30px;
color: #fff;
text-align: center;
display: block;
-webkit-border-radius: 3px;
-moz-border-radius: 3px;
border-radius: 3px;
background: #000;
text-decoration: none;
line-height: 30px;
}
</style>
</head>
<body>
<a class="link_class" href="http://www.w3cschool.cn">My Link</a>
</body>
</html>