body {
  font-family: "DINMittelschrift LT";
  background-color: black;
}

div.wall {
  position: relative;
  text-align: center;
  /* For debugging: */
  border: thin solid green;
}

div.cell {
  position: absolute;
  text-align: center;
  vertical-align: middle; 
  /*font-size: 36pt;*/
  color: #666666;
  background: #c0e0ff;
  /*
  border-top: 6px solid #cceeff;
  border-left: 6px solid #cceeff;
  border-bottom: 6px solid #bbdae9;
  border-right: 6px solid #bbdae9;
  */
}