.invoice {
    border-color: #000000;
    border-width: 0 0 1px 1px;
    border-style: solid;
}

.invoicecell {
    border-color: #000000;
    border-width: 1px 1px 0 0;
    border-style: solid;
    margin: 0;
    padding: 2px;
    text-align: center;
}

.invoicecellhead {
    border-color: #000000;
    border-width: 1px 1px 0 0;
    border-style: solid;
    margin: 0;
    padding: 2px;
    font-weight: bold;
    text-align: center;
}