clouded sky effect, based on http://www.clicktorelease.com/code/css3dclouds/
requestAnimationFrame
Just grab the sky.js and compile sky.less & include them in your html file.
Create a new sky object
var sky = new Sky({containerID : 'your-container-id'});
To start cloud rotation animation, call update() method
sky.update();
To stop cloud rotation animation, call stop() method
sky.stop();