body { position: relative; }
.back-to-top {
  position: absolute;
  left: 50%;
  transform: translateX(-50%);
  bottom: max(24px, env(safe-area-inset-bottom));
  z-index: 10;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 14px;
  min-height: 44px;
  padding: 10px 18px;
  border: 1px solid #ffffff40;
  border-radius: 30px;
  background: #12121466;
  color: #f4f1eb;
  font: 14px/1.2 "Barlow Condensed", sans-serif;
  letter-spacing: .06em;
  white-space: nowrap;
  cursor: pointer;
}
.back-to-top[hidden] { display: none; }
.back-to-top svg {
  width: 22px;
  height: 22px;
  fill: none;
  stroke: currentColor;
  stroke-width: 1.2;
  stroke-linecap: round;
  stroke-linejoin: round;
}
.back-to-top:focus-visible { outline: 2px solid #f4f1eb; outline-offset: 4px; }
/* Reserve space for the centered control at the page bottom. */
body.has-page-scroll > footer { padding-bottom: calc(88px + env(safe-area-inset-bottom)); }
@media (hover: hover) {
  .back-to-top:hover { background: #29292b99; border-color: #ffffff80; }
}
@media (max-width: 600px) {
  .back-to-top { bottom: max(16px, env(safe-area-inset-bottom)); }
}