#canvas {
  display: block;
  margin: 0 auto;
}

#control {
  position: absolute;
}

.cmd-btn {
  font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif;
  font-size: 24px;
  border: 3px solid #555;
  border-radius: 5px;
  color: #555;
  background: transparent;
  text-transform: uppercase;
  padding: 15px;
  width: 120px;
  text-align: center;
  display: inline
}

.cmd-btn:hover {
  cursor: pointer;
  color: #fff;
  background-color: #555;
}

.centered-on-page {
  text-align: center;
  display: table-cell;
  vertical-align: middle;
  font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
  font-size: xx-large;
  font-weight: bold;
}