JSFiddle - React, Tailwind, and code Playground

HTML

<div class="box"></div>
<div class="box"></div>
<div class="box"></div>
<div class="box"></div>
<div class="box"></div>

<hr>

<button id="addRandomClass">Добавить класс</button>

CSS

.box {
  display: inline-block;
  width: 100px;
  height: 100px;
  
  background: #000;
}

.box.active {
  background: green;
}

JavaScript

$('#addRandomClass').on('click', function(event){

	event.preventDefault();
  
  var elements = $('.box');
  
  var randomElementIndex = Math.round(Math.random() * (elements.length - 1 - 0) + 0);
  
  elements
  	.removeClass('active')
  	.eq(randomElementIndex)
    .addClass('active');

});