body {
  margin: 0;
  background: url("assets/bg.png") center/cover no-repeat black;
  font-family: monospace;
  color: crimson;
  text-align: center;
}

#menu, #game {
  margin-top: 80px;
}

button {
  padding: 12px 20px;
  margin: 6px;
  background: black;
  color: crimson;
  border: 1px solid crimson;
  cursor: pointer;
}

button:hover {
  background: crimson;
  color: black;
}

#heart {
  width: 160px;
  margin: 20px;
  animation: pulse 1s infinite;
}

@keyframes pulse {
  0% { transform: scale(1); }
  50% { transform: scale(1.15); }
  100% { transform: scale(1); }
}