JSFiddle - React, Tailwind, and code Playground

HTML

<link rel="stylesheet" href="//netdna.bootstrapcdn.com/bootstrap/3.0.0/css/bootstrap.min.css">
<script src="//ajax.googleapis.com/ajax/libs/jquery/1.10.2/jquery.min.js"></script>
<script src="//netdna.bootstrapcdn.com/bootstrap/3.0.0/js/bootstrap.min.js"></script>
<p> Click <b>menu</b> and use up/down keys to navigate </p>

<div class="btn-group">
    <button class="btn btn-default">1</button>
    <button class="btn btn-default">2</button>
    <button class="btn btn-default">3</button>
    <div class="btn-group open">
        <button class="btn btn-default dropdown-toggle" data-toggle="dropdown">menu</button>
        <ul class="dropdown-menu" role="menu">
            <li>
            <div class="btn-group open">
              <button href="#" class="btn btn-default dropdown-toggle" data-toggle="dropdown">one</button>
              <ul class="dropdown-menu" role="menu">
                <li> <a href="#">one</a> </li>
                <li> <a href="#">two</a> </li>
                <li> <a href="#">three</a> </li>
              </ul>
              </div>
            </li>
            <li> <a href="#">two</a> </li>
            <li> <a href="#">three</a> </li>
        </ul>
    </div>
</div>