Randomly generated designs inspired by Islamic art, specifically the decorative tilework known as Zellij, found on walls, floors, and fountains in Fez, Morocco.
The designs come in three sizes (20% small, 70% medium, 10% large). There is a 20% chance of an eightfold design appearing in a 2x2 square, and a 5% chance of a large sixteen-pointed rosette. 25% of designs will "shimmer" -- colours will vary subtly everywhere.
In fullscreen mode, you should be able to press the "s" key to download an SVG of your design.