JSFiddle - React, Tailwind, and code Playground

HTML

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

CSS

.b {
    background-color: #f00;
    height: 10px;
    margin-bottom: 5px;
}

JavaScript

(function(jQ){
    var $ = function(a){return jQ('#a').find(a);}
    // You can put any of your code here
    // Here goes an example
    $('.b').hide();
})($);