JSFiddle - React, Tailwind, and code Playground

HTML

<div id="target"></div>

CSS

body {
    padding:50px;
}

#target {
    background-color:gray;
    width:200px;
    height:200px;
    text-align:center;
    padding-top:50px;
    font-size:larger;
    font-weight:bold;
    color:white;
}

JavaScript

$( '#target' ).on( 'click', function( e ) {
    var x = e.pageX - this.offsetLeft;
    var y = e.pageY - this.offsetTop;

    $( this ).html(x +', '+ y);
});