/* Back to top — shared (Sobeys + About) */

.back-to-top {
  position: fixed;
  z-index: 80;
  bottom: max(20px, env(safe-area-inset-bottom, 0px) + 12px);
  right: max(20px, env(safe-area-inset-right, 0px) + 12px);
  display: inline-flex;
  align-items: center;
  gap: 7px;
  padding: 9px 14px 9px 12px;
  font-family: var(--mono-serif, "Helvetica Neue", Helvetica, Arial, sans-serif);
  font-size: 12px;
  font-weight: 500;
  font-style: normal;
  letter-spacing: 0.04em;
  text-transform: none;
  color: var(--about-ink-muted, rgba(0, 0, 0, 0.48));
  text-decoration: none;
  background: var(--about-chip-bg, rgba(253, 251, 247, 0.86));
  border: 1px solid var(--about-chip-border, rgba(0, 0, 0, 0.07));
  border-radius: 10px;
  box-shadow: 0 4px 18px rgba(0, 0, 0, 0.04);
  backdrop-filter: blur(10px) saturate(1.02);
  -webkit-backdrop-filter: blur(10px) saturate(1.02);
  opacity: 0;
  visibility: hidden;
  pointer-events: none;
  transform: translateY(8px);
  transition:
    opacity 0.42s cubic-bezier(0.22, 1, 0.36, 1),
    visibility 0.42s cubic-bezier(0.22, 1, 0.36, 1),
    transform 0.42s cubic-bezier(0.22, 1, 0.36, 1),
    color 0.25s ease,
    border-color 0.25s ease,
    box-shadow 0.32s ease,
    background 0.25s ease;
}

.back-to-top svg {
  flex-shrink: 0;
  opacity: 0.55;
  transition: opacity 0.25s ease, transform 0.32s cubic-bezier(0.22, 1, 0.36, 1);
}

.back-to-top.is-visible {
  opacity: 1;
  visibility: visible;
  pointer-events: auto;
  transform: translateY(0);
}

.back-to-top.is-visible:hover,
.back-to-top.is-visible:focus-visible {
  color: var(--page-ink);
  background: var(--about-chip-bg, rgba(252, 250, 246, 0.94));
  border-color: var(--about-chip-border, rgba(0, 0, 0, 0.1));
  box-shadow: 0 8px 26px rgba(0, 0, 0, 0.07);
}

.back-to-top.is-visible:hover svg,
.back-to-top.is-visible:focus-visible svg {
  opacity: 0.85;
}

.back-to-top.is-visible:active {
  box-shadow: 0 4px 16px rgba(0, 0, 0, 0.05);
}

.back-to-top:focus-visible {
  outline: 1px solid rgba(0, 0, 0, 0.2);
  outline-offset: 3px;
}

@media (max-width: 640px) {
  .back-to-top {
    bottom: max(16px, env(safe-area-inset-bottom, 0px) + 10px);
    right: max(16px, env(safe-area-inset-right, 0px) + 10px);
    padding: 8px 12px 8px 10px;
    font-size: 11px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .back-to-top {
    transition-duration: 0.05s;
  }

  .back-to-top svg {
    transition-duration: 0.05s;
  }
}