JSFiddle - React, Tailwind, and code Playground

HTML

<p>All '.item' highlighted :</p>
<div class="root" id="all">
    <div>
        <div class="item">
            <div class="item">
                <div>
                    <div>
                        <div class="item">
                            <div>
                                <div class="item elem">&nbsp;</div>
                            </div>
                        </div>
                    </div>
                </div>
            </div>
        </div>
    </div>
</div>
<p>What we think $.closest('.item') will return :</p>
<div class="root" id="desired-when-using-closest">
    <div>
        <div class="item">
            <div class="item">
                <div>
                    <div>
                        <div class="item">
                            <div>
                                <div class="item elem">&nbsp;</div>
                            </div>
                        </div>
                    </div>
                </div>
            </div>
        </div>
    </div>
</div>
<p>What $.closest('.item') returns :</p>
<div class="root" id="closest-returns-this">
    <div>
        <div class="item">
            <div class="item">
                <div>
                    <div>
                        <div class="item">
                            <div>
                                <div class="item elem">&nbsp;</div>
                            </div>
                        </div>
                    </div>
                </div>
            </div>
        </div>
    </div>
</div>

CSS

p{clear:both}
.root {margin:10px}
div {float:left; border:dashed 1px #aaa; min-width:50px; min-height:50px; padding:5px; background-color:#ffe}
.item {border-style:solid; border-color:#000}
.elem {display:block; border-width:2px; border-color:#070; width:50px; height:50px}
.found {background-color:lightgreen}

JavaScript

$('#all')
    .find('.item').addClass('found');

$('#desired-when-using-closest')
    .find('.elem')
    .parent().closest('.item').addClass('found');

$('#closest-returns-this')
    .find('.elem')
    .closest('.item').addClass('found');