html {
    background-color: Ivory;
}

.row{
    height: 50px;
    text-wrap: nowrap;
}

.cell{
    display: inline-block;
    width: 50px;
    height: 50px;
    font-size: 32px;
    line-height: 50px;
    text-align: center;
    box-sizing: content-box;
    border: 1px solid gray;
    text-wrap: nowrap;
}

.cell.gray{
    background: #444;
}

.cell.white{
    background: #EEE;
}
