.rainbow {
  /*font-family: monospace;*/
  animation: colorRotate .5s linear 0s infinite;
}

@keyframes colorRotate {
  from {
    color: #6666ff;
  }
  10% {
    color: #0099ff;
  }
  50% {
    color: #00ff00;
  }
  75% {
    color: #ff3399;
  }
  100% {
    color: #6666ff;
  }
}

button {
  border: none;
  cursor: pointer;
  appearance: none;
  background-color: inherit;
}