/* Floating scroll-to-top — site-wide reusable component */
.scroll-to-top {
  position: fixed;
  right: max(1rem, env(safe-area-inset-right, 0px));
  bottom: max(1rem, env(safe-area-inset-bottom, 0px));
  z-index: 900;
  width: 2.75rem;
  height: 2.75rem;
  padding: 0;
  border: 1px solid rgba(0, 0, 0, 0.12);
  border-radius: 9999px;
  background: #ffffff;
  color: #1d1d1f;
  box-shadow: 0 8px 24px rgba(0, 0, 0, 0.06), 0 2px 6px rgba(0, 0, 0, 0.04);
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  opacity: 0;
  visibility: hidden;
  transform: translateY(0.5rem) scale(0.92);
  pointer-events: none;
  transition:
    opacity 320ms cubic-bezier(0.25, 0.1, 0.25, 1),
    visibility 320ms cubic-bezier(0.25, 0.1, 0.25, 1),
    transform 320ms cubic-bezier(0.25, 0.1, 0.25, 1),
    background 200ms cubic-bezier(0.25, 0.1, 0.25, 1),
    color 200ms cubic-bezier(0.25, 0.1, 0.25, 1),
    box-shadow 200ms cubic-bezier(0.25, 0.1, 0.25, 1);
}

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

.scroll-to-top:hover {
  background: #1d1d1f;
  color: #ffffff;
  box-shadow: 0 16px 48px rgba(0, 0, 0, 0.08), 0 4px 12px rgba(0, 0, 0, 0.04);
}

.scroll-to-top:focus-visible {
  outline: 2px solid #1d1d1f;
  outline-offset: 2px;
}

.scroll-to-top__icon {
  font-size: 1.125rem;
  line-height: 1;
  font-weight: 600;
  user-select: none;
}

@media (min-width: 768px) {
  .scroll-to-top {
    width: 3rem;
    height: 3rem;
    right: max(1.5rem, env(safe-area-inset-right, 0px));
    bottom: max(1.5rem, env(safe-area-inset-bottom, 0px));
  }

  .scroll-to-top__icon {
    font-size: 1.25rem;
  }
}

@media (prefers-reduced-motion: reduce) {
  .scroll-to-top {
    transition: opacity 120ms linear, visibility 120ms linear;
    transform: none;
  }

  .scroll-to-top.is-visible {
    transform: none;
  }
}