/* Botón flotante · Volver arriba */
#sitio-volver-arriba {
  position: fixed;
  right: 22px;
  bottom: 22px;
  right: calc(22px + env(safe-area-inset-right, 0px));
  bottom: calc(22px + env(safe-area-inset-bottom, 0px));
  z-index: 1000;

  display: flex;
  align-items: center;
  justify-content: center;
  box-sizing: border-box;
  width: 48px;
  height: 48px;
  margin: 0;
  padding: 0;

  border: 1px solid rgba(255, 255, 255, .3);
  border-radius: 14px;
  background: #195998;
  color: #fff;
  box-shadow: 0 4px 14px rgba(32, 55, 80, .18);

  cursor: pointer;
  touch-action: manipulation;

  opacity: 0;
  visibility: hidden;
  pointer-events: none;
  transform: translateY(8px);

  transition:
    opacity .2s ease,
    transform .2s ease,
    background-color .2s ease,
    visibility .2s ease;
}

#sitio-volver-arriba.is-visible {
  opacity: 1;
  visibility: visible;
  pointer-events: auto;
  transform: translateY(0);
}

#sitio-volver-arriba:hover {
  background: #123e6a;
  transform: translateY(-2px);
}

#sitio-volver-arriba:focus-visible {
  outline: 3px solid #97e086;
  outline-offset: 4px;
}

#sitio-volver-arriba svg {
  display: block;
  width: 23px;
  height: 23px;
  pointer-events: none;
}

@media (max-width: 600px) {
  #sitio-volver-arriba {
    right: calc(14px + env(safe-area-inset-right, 0px));
    bottom: calc(14px + env(safe-area-inset-bottom, 0px));
    width: 46px;
    height: 46px;
    border-radius: 12px;
  }
}

@media (prefers-reduced-motion: reduce) {
  #sitio-volver-arriba {
    transition: none;
  }

  #sitio-volver-arriba:hover {
    transform: none;
  }
}

@media print {
  #sitio-volver-arriba {
    display: none !important;
  }
}