一，效果图。
二，代码。
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>CSS 盒子模型</title>
<style>
div.ex {
width: 220px;
padding: 10px;
border: 5px solid gray;
margin: 0px;
}
</style>
</head>
<body>
<img src="w3css.gif" width="250" height="250" />
<div class="ex">the picture above is 250px wide.the total width of this element is also 250px.</div>
</body>
</html>
参考资料:《菜鸟教程》