JSFiddle - React, Tailwind, and code Playground
by magizter
HTML
<ul>
<li><a href="#"><span class="menubutton">menu1</span></a></li>
<li><a href="#"><span class="menubutton">menu2</span></a></li>
<li><a href="#"><span class="menubutton">menu3</span></a></li>
</ul>
CSS
.contactmenu {background-color:#FF0000;color:#fff}
JavaScript
$(document).ready(function(){
$("span.menubutton:last").addClass('contactmenu');
});