Try it at vrugtehagel.nl/mastermind!
This is somewhat of a sequel to my pure CSS calculator. I wanted to do something showing off the power of CSS while also being a bit more fun than a calculator. So, this version of Mastermind was born.
It's a bit more polished than the calculator, but the code is still spaghetti because using only HTML and CSS to write a functional page is not generally a maintainable way of doing things.
Also, accessibility was basically thrown out the window. It works only for users with perfect vision. Not very inclusive of me, I know...
Anyway, enjoy!