JSFiddle - React, Tailwind, and code Playground

HTML

<canvas id="canvas" width="400" height="400"></canvas>

CSS

/*Simple reset*/
* {margin: 0; padding: 0;}

body {
	/*You can use any kind of background here.*/
	background: #6b92b9;
}
canvas {
	display: block;
}

JavaScript

//canvas init
var canvas = document.getElementById("canvas");
var ctx = canvas.getContext("2d");

//canvas dimensions
var W = window.innerWidth;
var H = window.innerHeight;
canvas.width = W;
canvas.height = H;

//snowflake particles
var mp = 25; //max particles
var particles = [];
for (var i = 0; i < mp; i++) {
    particles.push({
        x: Math.random() * W, //x-coordinate
        y: Math.random() * H, //y-coordinate
        r: Math.random() * 4 + 1, //radius
        d: Math.random() * mp, //density
        color: "rgba(" + Math.floor(Math.random()*255) +
                ", " + Math.floor(Math.random()*255) + ", 255, 0.8)"
    })
}

//Lets draw the flakes
function draw() {
    ctx.clearRect(0, 0, W, H);


    for (var i = 0; i < mp; i++) {
        var p = particles[i];
        ctx.fillStyle = p.color;
        ctx.beginPath();        
        ctx.moveTo(p.x, p.y);
        ctx.arc(p.x, p.y, p.r, 0, Math.PI * 2, true);
        ctx.fill();
    }
    
    update();
}

//Function to move the snowflakes
//angle will be an ongoing incremental flag. Sin and Cos functions will be applied to it to create vertical and horizontal movements of the flakes
var angle = 0;

function update() {
    angle += 0.01;
    for (var i = 0; i < mp; i++) {
        var p = particles[i];
        //Updating X and Y coordinates
        //We will add 1 to the cos function to prevent negative values which will lead flakes to move upwards
        //Every particle has its own density which can be used to make the downward movement different for each flake
        //Lets make it more random by adding in the radius
        p.y += Math.cos(angle + p.d) + 1 + p.r / 2;
        p.x += Math.sin(angle) * 2;

        //Sending flakes back from the top when it exits
        //Lets make it a bit more organic and let flakes enter from the left and right also.
        if (p.x > W + 5 || p.x < -5 || p.y > H) {
            if (i % 3 > 0) //66.67% of the flakes
            {
                particles[i] = {
   ...