change a doms element width code example

Example 1: javascript set element width

document.getElementById("myElID").style.width = "100px";

Example 2: get width of a dom element js

// Get Content + Padding + Border
let box = document.querySelector('div');
let width = box.offsetWidth;
let height = box.offsetHeight;

// Get Content + Padding only
let box = document.querySelector('div');
let width = box.clientWidth;
let height = box.clientHeight;