Reflex Rush

Prompt

Build a public reaction-time website game called **Reflex Rush**.

Requirements:

* Give players a start screen and a clearly explained reaction challenge.
* Start each round with a waiting period.
* Change the screen when the player should react.
* Players must tap as quickly as possible when the signal appears.
* Penalize players who tap before the signal.
* Run multiple rounds and calculate the player's average reaction time in milliseconds.
* Display the best reaction time, average reaction time, and final score.
* Allow players to restart and try to beat their personal best.
* Include a leaderboard if a real backend is available.
* Use a full-screen black reaction arena with neon green and red accents.
* Make the central reaction area large and easy to tap on a phone.
* Ensure the game works on desktop and mobile.
* Do not count a premature tap as a successful reaction.