It's a simple calculator with a flat design that works in the game "Onset".
Created by ShotenDev.
Put the folder "calculator" in the folder "packages" on your server.
Don't forget to add this package in server_config.json :
"packages": [
"default",
"freeroam",
"sandbox",
"calculator"
],
The default key in game is "H", you can change the key in "client.lua" file.
You can also change the text in "index.html" file.
It's of course possible to adapt this system to integrate it into a telephone for example.