/* Fixed vertical behavior stays with the existing To Top controller. */
body a.totop {
  --twoip-totop-button-size: 55px;
  --twoip-totop-container-gap: 20px;
  width: var(--twoip-totop-button-size);
  height: var(--twoip-totop-button-size);
  /* Percentages use the layout viewport, excluding the scrollbar unlike 100vw. */
  right: max(
    calc(var(--twoip-totop-right) + env(safe-area-inset-right, 0px)),
    calc((100% - min(100%, var(--twoip-container-large))) / 2 + var(--twoip-grid-gutter) / 2 - var(--twoip-totop-container-gap) - var(--twoip-totop-button-size))
  );
}