#randomart tr:nth-child(even) td:nth-child(even),
#randomart tr:nth-child(odd) td:nth-child(odd)
{
  background-color: #fefefe;
}

#randomart td {
  width: 1em;
  font-family: "monospace";
  text-align: center;
}

#randomart tr {
  height: 1.5em;
}