#board {
    display: flex;
    align-items: center;
    justify-content: center;
    flex-direction: column;
}
.tile {
    background-color: grey;
    width: 100px;
    height: 100px;
    border: 5px black solid;
    text-align: center;
    font-size: 100px; }
.row {
    display: flex;
    justify-content: center;
    align-items: center;
    flex-direction: row;
}