table.sortable tbody {
    counter-reset: sortabletablescope;
}
table.sortable thead tr::before {
    content: "";
    display: table-cell;
}
table.sortable tbody tr::before {
    content: counter(sortabletablescope);
    counter-increment: sortabletablescope;
    display: table-cell;
}


table.sortable tbody tr:nth-child(2n) td {
  background: #00FF00;
}
table.sortable tbody tr:nth-child(2n+1) td {
  background: #00FFFF;
}