JSFiddle - React, Tailwind, and code Playground

HTML

<ul>
    <li><a href="#"></a>a</li>
    <li><a href="#"></a>b</li>
    <li><a href="#"></a>c</li>
    <li><a href="#"></a>d</li>
    <li><a href="#"></a>e</li>
</ul>

CSS

li {
    background-color: blue;
    width: 30px;
    margin-bottom: 2px;
}

JavaScript

$('li').click(
    function () {
        alert($(this).index());
    }
    );