It's a pretty simple puzzle. 3x3 grid with 3 colors (will eventually be able to make it more dimensions/colors)
When a square is clicked on, that square and the squares above, below, to the right, and to the left if the exist are cycled forward one color. The last color wraps back to the first.
The goal is to make the grid all one color.
Icons are from the Remix Line Interface Icons collection.