This is a cool and nostalgic take on Minesweeper. I like the general quality improvements and the unique twist on it. My only issue was that the player isn't protected on the first box, and there were several times when I'd start a new game, and the first box I clicked was a game over. That's why I'm thankful for the Undo and Restart options that you added.
Great work on this!
Please check out and rate my game. =)