JSFiddle - React, Tailwind, and code Playground

HTML

<li class="nav" id="1"><a href="#detail">a</a></li>
<li class="nav" id="2"><a href="#detail">b</a></li>
<li class="nav" id="3"><a href="#detail">c</a></li>

JavaScript

$('li.nav a').on('click', function (e) {
  e.preventDefault();
  var id = $(this).parent().attr('id');
  alert(id);
});