body {
  text-align: center;
  font-family: sans-serif;
}

body.playing .hidden-in-game {
  visibility: hidden;
}

.only-in-game {
  display: none;
}

body.playing .only-in-game {
  display: block;
}

#reload {
  position: absolute;
  right: 1rem;
  top: 1rem;
  font-size: xx-large;
}

a {
  text-decoration: none;
  color: #222222;
}

form {
  margin-bottom: 1rem;
}

.field {
  margin-top: 1rem;
  margin-left: auto;
  margin-right: auto;
  border-collapse: collapse;
}

.cell {
  border: 2px solid #000000;
  width: 20px;
  height: 20px;
}

.fixed {
  background-color: #000000;
}

.empty {
  background-color: #ffffff;
}

.navigation {
  margin-top: 1rem;
}

.navigation a {
  margin-left: 0.4rem;
  margin-right: 0.4rem;
}

.footer {
  font-size: small;
  margin-top: 1rem;
}

div.block {
  position: absolute;
  background-color: #cbc7ffee;
  cursor: move;
  margin: 0;
  padding: 0;
  border: 2px solid #000000;
}