[popover] {
  opacity: 0;
  scale: 0.8;
  transition: 
    opacity 0.3s ease,
    scale 0.3s ease,
    display 0.3s allow-discrete;
}

[popover]:popover-open {
  opacity: 1;
  scale: 1;

  @starting-style {
    opacity: 0;
    scale: 0.8;
  }
}