span {
    padding: 0.05rem 0.6rem;
    border-width: 2px;
    border-color: black;
    border-style: solid;
}

.rot {
    background-color: red;
}

.gelb {
    background-color: yellow;
}

.gruen {
    background-color: green;
}

tr {
    margin: 0.6rem;
}