/* ============================================
   BORTLE CERO — Botón "Ir arriba" (To Top)
   Estructura fija; color/tamaño/posición vienen de variables inline
   (--tt-*) que pone bc_totop_render() según el Customizer.
   ============================================ */

.bc-totop {
  position: fixed;
  bottom: 24px;
  z-index: 90;
  width: var(--tt-size, 46px);
  height: var(--tt-size, 46px);
  padding: 0;
  border: none;
  border-radius: 50%;
  background: var(--tt-bg, #7ba8d4);
  color: var(--tt-icon, #080c14);
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  box-shadow: 0 6px 20px rgba(0, 0, 0, 0.35);
  opacity: 0;
  visibility: hidden;
  transform: translateY(12px);
  transition: opacity 0.25s ease, transform 0.25s ease, filter 0.15s ease;
}

.bc-totop--right  { right: 24px; }
.bc-totop--left   { left: 24px; }
.bc-totop--center { left: 50%; margin-left: calc(var(--tt-size, 46px) / -2); }

.bc-totop.is-visible {
  opacity: 1;
  visibility: visible;
  transform: none;
}

.bc-totop:hover { filter: brightness(1.08); transform: translateY(-2px); }
.bc-totop:focus-visible { outline: 2px solid var(--bc-estrella, #b8d4f0); outline-offset: 2px; }

.bc-totop svg { display: block; width: 52%; height: 52%; }

@media (max-width: 600px) {
  .bc-totop { bottom: 16px; }
  .bc-totop--right { right: 16px; }
  .bc-totop--left  { left: 16px; }
}

@media (prefers-reduced-motion: reduce) {
  .bc-totop { transition: opacity 0.2s ease; transform: none; }
  .bc-totop.is-visible { transform: none; }
  .bc-totop:hover { transform: none; }
}