Forums → Programming Forum → Looking for Reaction Time tutorial

Hiya Everybody, Trying to learn some game design etc as a free time hobby and I wanna try my hand at making a small reaction time/quick draw game by leveling up and each level having a shorter reaction time.

For example, like Kupo's game here:
https://armorgames.com/play/2899/brawl-royale

Or these games:
http://www.bullettimereaction.com/
https://www.youtube.com/watch?v=3BeYJQrtT04

So basically it needs a timer, but when it goes over that timer it's game over (getting shorter with each good run)
Not some prompt that appears on a timer starts and stops to show you the time of your reaction (like this: https://codepen.io/cliff538/pen/Eslxr)

Tyring to search for it on google, but I don't have any succes.
I just stumble upon other quick draw games or apps or something not game related.

I have most of the adobe programs to draw (that's not a problem) but I'm looking for a coding tutorial for this. I can code in flash and html/css so either one of those languages would be great. Anyways thanks for the help.