JSFiddle - React, Tailwind, and code Playground

HTML

<!DOCTYPE html>
<html>
    <head></head>
    <body>
        <input type="radio" name="test" checked="checked" id="id-test" />
        <input type="radio" name="test" />
    </body>
</html>

CSS

input:checked {width: 200px; outline: 1px solid red;}

JavaScript

alert($('#id-test').css('width'));