let a=0;
function setup() {
createCanvas(400, 400);
//background(120);
}
function draw() {
fill(125,random(180),125)
a+=0.35;
push();
translate(mouseX,mouseY);
scale(random(6));
rotate(a);
scale(map(mouseX,0,400,0,0.3));
rect(0, 0, 50, 50);
}
<script src='https://cdn.jsdelivr.net/npm/p5@1.1.9/lib/p5.min.js'></script>