Fun! It would add to the challenge to have the yellow box move through the pieces AT RANDOM, rather than in order - but I realize that might be difficult to set up.
Nice. Although two things: first, it gets a bit old to type in "pawn" 16 times, or even use copypaste for it all. Second, seeing just one set of pieces wasn't sure if I was seeing black or white and then knowing the placement of king/queen gets harder. Unless you are used to computer chess I guess.
I was very confused the first time because I thought you meant to label each piece specifically, e.g. queenside black rook, kingside white bishop, white d pawn, etc.
if your bored someday...? :-)