mrprogre/brain-shake-game ? reverse-engineered prompt

Build me a simple Java desktop game for kids that helps them learn numbers in a fun way.

I want two main modes, a child friendly learning mode and a harder brain training mode for quick mental practice. The game should speak the numbers in both Russian and English, show the numbers clearly on screen, and let the player hear them as they play. Keep the interface very simple and colorful so it feels good for children, but still usable for adults who want the training mode.

Make it feel like a small standalone app that opens in a window and is easy to run. If you need to check anything about sound or GUI behavior, look up the current docs online and then build it cleanly. Please include the full working implementation and make sure it is polished enough to launch as a finished game.