.page-top-marker { position: absolute; top: 0; left: 0; width: 1px; height: 1px; pointer-events: none; }
.back-to-top {
  position: fixed;
  z-index: 38;
  right: 22px;
  bottom: 22px;
  width: 48px;
  height: 48px;
  border: 1px solid rgba(23, 23, 26, .12);
  border-radius: 50%;
  display: grid;
  place-items: center;
  color: #fff;
  background: #17171a;
  box-shadow: 0 12px 34px rgba(23, 23, 26, .18);
  font: 700 24px/1 Arial, sans-serif;
  cursor: pointer;
  transition: transform 180ms cubic-bezier(.2,.8,.2,1), background 180ms ease, opacity 180ms ease;
}
.back-to-top:hover { transform: translateY(-3px); background: #6545d7; }
.back-to-top:active { transform: translateY(-1px) scale(.97); }
.back-to-top[hidden] { display: none; }
@media (max-width: 760px) { .back-to-top { right: 14px; bottom: 82px; width: 44px; height: 44px; } }
@media (prefers-reduced-motion: reduce) { .back-to-top { transition: none; } }