body {
    font-family: sans-serif;
    background-color: #129997;
    color: #e8922a;
    margin: 0%;
}

td {
    width: 2rem;
    height: 2rem;
}

td.on {
    background-color: #000;
}
td.off {
    background-color: #fff;
}

.slider {
    width: 20rem;
}