JSFiddle - React, Tailwind, and code Playground

HTML

<script type="text/javascript">
$(document).ready(function(){
    $('input[name="auth"]').change(function(){
        $('#changestatus').find('input').prop('disabled', $(this).prop('checked'));
    });
});
</script>
<form action="#" method="POST" id="mm_config">
    <input name="auth" type="checkbox" value="yes" /><br />
    <span id="changestatus">
        <input type="text" name="user" id="textfield" value="test" />
        <input type="password" name="pass" id="textfield" value="test" />
    </span>
</form>