JSFiddle - React, Tailwind, and code Playground

HTML

<a href="#" id="tik">Tıkla</a>
<div id="kare"></div>

CSS

#kare{
        width: 100px;
        height: 100px;
        background-color: #ddd;
		left:5px;
    }

JavaScript

$(document).ready(function(){
		$("#tik").click(function(){
			var deger = $("#kare").css("width");
			alert(deger);
        })	
			
    });