JSFiddle - React, Tailwind, and code Playground

HTML

<div></div>

CSS

div {
  border: 1px solid;
  height: 120px;
  width: 130px;
}

JavaScript

let div = document.querySelector("div");

window.addEventListener("load", function(event) {
	const element_box = div.getBoundingClientRect();
  console.log(`Original element height: ${element_box.height}`)
  element_box.height += 50;
  console.log(`New element height: ${element_box.height}`)
})