/* Scroll-to-top button (visible only after scrolling) */
/* Theme-aware accent:
   - Light: azul (accent)
   - Dark/Noche: naranja pastel (accent-warm)
*/
html[data-theme="light"]{
  --scrolltop-accent: var(--accent);
  --scrolltop-accent-rgb: var(--accent-rgb);
}

html[data-theme="dark"]{
  --scrolltop-accent: var(--accent-warm);
  --scrolltop-accent-rgb: var(--accent-warm-rgb);
}

/* Auto / sin data-theme: azul por defecto, naranja si el sistema está en oscuro */
html[data-theme="auto"],
html:not([data-theme]){
  --scrolltop-accent: var(--accent);
  --scrolltop-accent-rgb: var(--accent-rgb);
}

@media (prefers-color-scheme: dark){
  html[data-theme="auto"],
  html:not([data-theme]){
    --scrolltop-accent: var(--accent-warm);
    --scrolltop-accent-rgb: var(--accent-warm-rgb);
  }
}

.scrollTop{
  position: fixed;
  right: 16px;
  bottom: 16px;
  z-index: 50;

  display: inline-flex;
  align-items: center;
  justify-content: center;

  width: 44px;
  height: 44px;

  border-radius: 14px;
  border: 1px solid var(--border);
  background: var(--surface);
  color: var(--scrolltop-accent, var(--accent, #5f86b6));

  box-shadow: 0 10px 24px rgba(0,0,0,.18);
  cursor: pointer;

  opacity: 0;
  transform: translateY(8px) scale(.98);
  transition: opacity .16s ease, transform .16s ease, background .16s ease, border-color .16s ease;
}

.scrollTop span{
  font-size: 18px;
  font-weight: 700;
  line-height: 1;
}

.scrollTop:hover{
  background: var(--surface-2, rgba(255,255,255,.06));
  border-color: var(--scrolltop-accent, var(--accent, #5f86b6));
}

.scrollTop:focus-visible{
  outline: 2px solid var(--scrolltop-accent, var(--accent, #5f86b6));
  outline-offset: 2px;
}

.scrollTop.is-visible{
  opacity: 1;
  transform: translateY(0) scale(1);
  border-color: rgba(var(--scrolltop-accent-rgb, var(--accent-rgb, 95 134 182)) / 0.55);
}

/* Reduce motion */
@media (prefers-reduced-motion: reduce){
  .scrollTop{
    transition: none;
  }
}