I built a free, open-source tool to improve my Chess Vision and Coordinate memory. Looking for feature ideas!

Hi everyone,
I've been trying to improve my calculation skills, but I realized I was struggling with visualizing the board (knowing instantly if 'e4' is white or black) and finding coordinates quickly without looking at the numbers.
So, I decided to build a simple web app to train these specific skills.

It’s called Chess Warmup.

It currently has 4 modes:

• Color Memory: Guess if a square is White or Black.
• Coordinate Finder: Click the correct square as fast as possible.
• Piece Movement: Coordinate work with the appropriate moves of chess pieces.
• Ghost Mode: The hardest one! Coordinates are hidden, forcing you to use your instinct.

It also tracks your stats and shows a heatmap of your weak squares after each session. It's completely free, no ads, and no sign-up required.

I would love to hear your feedback: What other training modes or features would help you as a beginner?

Here is the link to try it: Live Site And here is the source code on GitHub if you want to contribute: Github Repo