ColorFilter Puzzle

Each color viewed is a combination of four translucent colored tiles. There are only four colors involved, but it is only when all four are different that the color shown is that of the border.
The object is to make the whole grid the color of the border by clicking on the dots.
Each dot is centered on a panel whose image has the four colors each in a quadrant. Clicking the dot rotates the panel for that dot, but also rotates in the opposite direction any horizontally or vertically adjacent panel.

Press 'r' to randomize puzzle (chooses five random dots to press a random number of times).
Press 'r' multiple times to increase difficulty.