JSFiddle - React, Tailwind, and code Playground

HTML

<script src="http://cdn.jquerytools.org/1.2.7/full/jquery.tools.min.js&quot;"></script>
<form name="form1" method="post" action="">
    <input type="radio" name="radio" id="jqt3" value="jqt3">
    <label for="jqt3">label</label>
</form>

CSS

.active {
    width: 100px;
    height: 100px;
    outline: 1px solid red;
}

JavaScript

$(document).ready(function(){
    $("#jqt3").addClass("active");
});