JSFiddle - React, Tailwind, and code Playground

HTML

<span class="testClass">d</span>
     <span class="testClass">d</span>
     <span class="testClass">d</span>
     <span class="testClass">d</span>

    <div id="outer">
        <span class="testClass">d</span>
        <span class="testClass">d</span>
        <span class="c">d</span>
        <span class="testClass">d</span>
        <span class="testClass">d</span>
        <span class="testClass">d</span>
        <span class="c">d</span>
        <span class="testClass">d</span>
        <span class="testClass">d</span>
        <span class="testClass">d</span>
    </div>

CSS

.testClass{
    
    color:red;

}

.c{
    
    color:blue;

}

JavaScript

$('#outer').removeClass('testClass');