.to-top {
  position: fixed;
  right: 28px;
  bottom: 36px;
  z-index: 100;
  cursor: pointer;
  opacity: 0;
  visibility: hidden;
  transform: translateY(12px) scale(.94);
  transition: opacity .25s ease, visibility .25s ease, transform .25s ease;
}
.to-top--visible { opacity: 1; visibility: visible; transform: translateY(0) scale(1); }
.to-top--visible:active { transform: scale(.96); }
@media (prefers-reduced-motion: reduce) {
  .to-top { transition: none; }
}