I originally wrote this out of boredom back when I was in the Korean military, sometime in 2022. Coding this was one heck of a challenge, because Internet access wasn't readily available. As such, I had to go back and forth to debug any JS issues and figure out the CSS styling, as I wasn't exactly a designer. I finished the MVP in about a week, although the polish took the coming months to add in, whenever I got bored (which was a lot… you don't go to the military for fun). It's not perfect, although I hope that you could appreciate the struggle of writing such a simple thing in a less-than-ideal environment.
There are some changes I made compared to the original version I took out of the military: