Move your cursor to change the color of the stripe: The X-axis controls the hue, the Y-axis the brightness, and the saturation fluctuates regularly. Press space to pause the fluctuation, and again to resume. Click to create a stripe, left arrow to delete last stripe, and right arrow to restore stripes. On a mobile, tap the rotating colored square to open buttons such as pause/resume saturation blinking, undo and redo. Tap it again to hide them.
