canvas {
  display: block;
}

.center {
  display: flex;
  justify-content: center;
  margin: 12px auto 12px auto;
}

.class {
  display: block;
}

.button {
  margin: 0 3px 0 3px;
  background-color: #CCCCCC;
  border: 1px solid #CCCCCC;
  border-radius: 2px;
  padding: 0 10px;
  text-align: center;
  display: inline-block;
  font-size: 16px;
}

.button:hover {
  cursor: pointer;
  background-color: #999999;
}

.disabled {
  color:  grey;
  opacity: 0.4;
  pointer-events: none;
}