JSFiddle - React, Tailwind, and code Playground

HTML

<div class="container">
  <div class="block"></div>
  <div class="block"></div>
  <div class="block"></div>
  <div class="block"></div>
</div>

CSS

*, *:before, *:after {
    box-sizing: border-box;
}
.block {
  width: 60px;
  height: 60px;
  background-color: red;
  display: inline-block;
  cursor: pointer;
}
.myClass{
  background-color: green;
}

JavaScript

$(document).ready(function() {
	$('.container .block').on('click', function() {
		$('.container .block').removeClass('myClass');
    $(this).addClass('myClass');
	});
});