// require() some stuff from npm (like you were using browserify)
// and then hit Run Code to run it on the right
var _ = require('lodash');
var x = 1000;

function randomColor(){
  return '#' + ((1<<24) * Math.random()|0).toString(16);
}

var generateGrid = function(){
  var elem = document.createElement('div');
  elem.style.background = randomColor();
  document.body.appendChild(elem);
  if (--x > 0)
  	requestAnimationFrame(generateGrid);
};

generateGrid();