JSFiddle - React, Tailwind, and code Playground

HTML

<canvas id="canvas" width="480" height="320"></canvas>

CSS

canvas {
    display: block;
    margin: 10px auto;
    border: 3px solid black;
    border-radius: 10px;
    height: 50%;
    width: 75%;
}

JavaScript

var canvas = document.getElementById("canvas");

canvas.width = canvas.offsetWidth;
canvas.height = canvas.offsetHeight;