That sounds like a great idea for a fun and interactive birthday countdown app! 🎉 A few common issues could be around handling date formats, accounting for leap years, or calculating the difference between now and the next birthday correctly (especially if the birthday already passed this year).

When you get it working, it could even be expanded to show привітання з днем народження хлопчика школяра (birthday greetings for a school-age boy) or generate a custom birthday message along with the countdown — that would make it more engaging for younger users!

If you’d like, feel free to share your current code — happy to take a look and help debug it with you!