Try viewing it on a phone. It says you have to use a desktop.
CSS animations work, any individual browser bugs notwithstanding. The nice thing about this site is that you don't have to guess all the CSS `@keyframes` and `animation` parameters to match some vision in your head, but you can visually experiment.
The actual value of this site is the interface, and I can see why it would be hard to make it work specifically for mobile devices.
> Mobile version is unavailable at the moment. To experience Animista try it on your desktop.
The text is unselectable on mobile as well.