JSFiddle - React, Tailwind, and code Playground

HTML

<script src="http://code.jquery.com/jquery-2.0.3.min.js"></script>
<input type="button" value="Click me" />

<div class="a">
    <div class="b"></div>
</div>

<pre class="output"></pre>

JavaScript

$(function () {

    $('input[type="button"]').on('click', function () {
        var result = $('.b').closest('.a');
        if (1 == result[0]) {
            $('.output').append("Hm\n");
        }
    });
    
});