#board { border: 1px solid black; }
    #board td { width: 50px; height: 50px; -moz-border-radius: 25px; -webkit-border-radius: 25px; border-radius: 25px; }
    #board .player1 { background-color: red; }
    #board .player2 { background-color: black; }
    #board.gameover td { opacity: .5; }
    #board.gameover td.win { opacity: 1; }