JSFiddle - React, Tailwind, and code Playground

HTML

<canvas id="canvas">
</canvas>

CSS

#canvas {
    position: absolute;
    top: 0;
    left: 0;
    z-index: -1;
}

JavaScript

$(document).ready(function() {
    
    // Initialise canvas
    initCanvas();
    $(window).resize(function() {
        initCanvas();
    });

    // Draw on canvas
    
    var c = document.getElementById("canvas");
    var ctx = c.getContext("2d");
    ctx.moveTo(0,0);
    ctx.lineTo(200,100);
    ctx.stroke();
    
});

function initCanvas() {
    var canvas = $('#canvas'),
        w = $(window);
    
    var dimensions = {
        width: w.width(),
        height: w.height()
    };
    
    canvas.css(dimensions).prop(dimensions);
}