@keyframes heart {
  0%, 40%, 80%, 100% {
    transform: scale(1);
  }
  20%, 60% {
    transform: scale(1.15);
  }
}
.heart {
  animation: heart 1000ms infinite;
}

.copy-btn {
  position: absolute;
  top: 6px;
  right: 6px;
}