JSFiddle - React, Tailwind, and code Playground
HTML
<ul>
<li>What is jQuery?</li>
<li>What is HTML?</li>
<li>What is CSS</li>
</ul>
CSS
ul{counter-reset:mycounter}
ul li:after{counter-increment:mycounter;content:" (" counter(mycounter) " of " attr(data-total) ")"}
JavaScript
$(function(){
var o = $('li');
o.attr('data-total',o.length);
})