This idea is really really interesting. I think a lot of different ciphers can be explored with this alchemical setting.
That said, the game should teach you how to solve a puzzle, not just require to solve it. Like, I had to open numbers to letters converter on another tab, and just gave up on quadrilateral equation because I can’t solve it inside the game without knowing what to door googling it.
I quite like the graphics and the feedback to player actions. Font is a little hard to read sometimes.
Also, I suggest adding hits and maybe even full solutions to ciphers in the description with some sort of spoiler tag. Because I think people will be curious to see a solution to something they couldn’t figure out.