.cell {
    width: 30px;
    height: 30px;
    border: 1px solid #ccc;
    display: inline-block;
    text-align: center;
    vertical-align: middle;
    line-height: 30px;
    font-size: 16px;
    cursor: pointer;
}

.cell.hidden {
    background-color: #eee;
    color: #333;
}

.cell.mine {
    background-color: #ff6347;
    color: #fff;
}

.cell.lose {
    background-color: #ff6347;
    color: #fff;
    border: 1px solid #333;
}

h3 {
    margin-top: 20px;
}