body {
    font-family: "Helvetica", sans-serif;
}

td {
    width: 30px !important;
    height: 30px !important;
    text-align: center;
    color: black;
    border: 1px solid black;
}

.bomb {
    background-color: red;
}

.covered {
    background-color: darkgray;
}

.uncovered {
    background-color: lightgray;
}