body {
  font-family: sans-serif;
  font-size: 14px;
  color: black;
}
div#lauks {
  width: 780px;
  height: 780px;
  margin: 1% auto;
  border: 1px #666 solid;
  padding: 5px;
}
h1 {
  text-align: center;
}
span.field {
  display:inline-block;
  color: #333;
  width: 70px;
  height: 70px;
  text-align: center;
  vertical-align: middle;
  border: 1px #000 solid;
  background-color: #ccc;
  margin: 3px;
}
span.tailix {
  background-color: red;
}
span.headix {
  background-color: green;
}