<!DOCTYPE html>
<html>
<head>
    <meta charset="utf-8"> 
    <title>Bootstrap 实例 - 按钮大小</title>
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    <script src="https://cdn.staticfile.org/jquery/2.1.1/jquery.min.js"></script>
    <script src="https://cdn.staticfile.org/twitter-bootstrap/3.3.7/js/bootstrap.min.js"></script>
</head>
<body>

<p>
   <button type="button" class="btn btn-primary btn-lg">大的原始按钮</button>
   <button type="button" class="btn btn-default btn-lg">大的按钮</button>
</p>
<p>
   <button type="button" class="btn btn-primary"> 默认大小的原始按钮</button>
   <button type="button" class="btn btn-default"> 默认大小的按钮</button>
</p>
<p>
   <button type="button" class="btn btn-primary btn-sm">小的原始按钮</button>
   <button type="button" class="btn btn-default btn-sm">小的按钮</button>
</p>
<p>
   <button type="button" class="btn btn-primary btn-xs">特别小的原始按钮</button>
   <button type="button" class="btn btn-default btn-xs">特别小的按钮</button>
</p>
<p>
   <button type="button" class="btn btn-primary btn-lg btn-block">块级的原始按钮</button>
   <button type="button" class="btn btn-default btn-lg btn-block">块级的按钮</button>
</p>

</body>
</html>