JSFiddle - React, Tailwind, and code Playground

HTML

<input type="button" value="Click Me" id="button" />

<div id="test">
    <a href="#" class="ignor">One</a>
    <a href="#" class="ignor">Two</a>
    <a href="#" class="ignor">Three</a>
</div>

JavaScript

$('#button').click(function(){
    $('#test a:nth-child(2)').css('font-size', '55px'); 
});


$('.ignor').click(function(e){
    e.preventDefault();
    var index = $('a').index(this);
    var parent = $(this).parent().attr('id');
    alert('You clicked on index: '+index);
    highlightMe(parent, index+1);
});


function highlightMe(parent, child){
    $('#'+parent+' a:nth-child('+child+')').css('font-size', '55px'); 
}