JSFiddle - React, Tailwind, and code Playground

JavaScript

var paper = Raphael(0, 0, 500, 500);

var mysquare = paper.rect(25, 25, 250, 250).attr("fill", "red");

function turnMeBlue(e) {
   this.attr("fill", "green");     
}

mysquare.click(turnMeBlue);