body {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, 'Open Sans', 'Helvetica Neue', sans-serif;
  color: green;
}


/* create cool rotating effect if mouse gets over elemet with class .logo */

@keyframes rotate {
  0% {
    transform: rotate(0deg);
  }
  100% {
    transform: rotate(360deg);
  }
}

.logo:hover {
  animation: rotate 1s linear infinite;
}

header {
  -webkit-app-region: drag;
}

header button, header img {
  -webkit-app-region: no-drag;
  cursor: pointer;
}