A square (like e4) will appear. Click Light if you think it’s a light square, or Dark if you think it’s a dark one. The board flashes briefly to show the answer, then a new square appears.
Tips for Training:
Try to see the colour instantly. Don’t calculate by file and rank.
Visualize the board in your mind instead of relying on the screen.
Hide the board to practice pure visualization.
Focus on smaller sections (like one rank or file) to build accuracy.