.iosum-muestra-sello,
.iosum-muestra-aviso {
  position: fixed;
  z-index: 2147483000;
  font: 500 12px/1.3 -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
  letter-spacing: 0;
  text-transform: none;
  color: #fff;
  background: rgba(18, 18, 20, 0.86);
  -webkit-backdrop-filter: blur(8px);
  backdrop-filter: blur(8px);
  box-shadow: 0 2px 10px rgba(0, 0, 0, 0.18);
}

/* Pestaña vertical pegada al borde izquierdo: no tapa barras de compra ni botones flotantes. */
.iosum-muestra-sello {
  left: 0;
  top: 50%;
  transform: translateY(-50%) rotate(180deg);
  writing-mode: vertical-rl;
  display: flex;
  align-items: center;
  gap: 4px;
  width: 26px;
  padding: 12px 0 4px;
  border-radius: 8px 0 0 8px;
}

.iosum-muestra-sello a {
  color: #fff !important;
  text-decoration: none !important;
  white-space: nowrap;
}

.iosum-muestra-sello button {
  all: unset;
  cursor: pointer;
  width: 22px;
  height: 22px;
  display: grid;
  place-items: center;
  font-size: 15px;
  line-height: 1;
  opacity: 0.7;
}

.iosum-muestra-sello button:hover,
.iosum-muestra-sello button:focus-visible {
  opacity: 1;
}

.iosum-muestra-aviso {
  left: 50%;
  bottom: 24px;
  max-width: min(420px, calc(100vw - 32px));
  padding: 12px 16px;
  border-radius: 10px;
  font-size: 14px;
  line-height: 1.4;
  text-align: center;
  opacity: 0;
  transform: translate(-50%, 8px);
  transition: opacity 0.2s ease, transform 0.2s ease;
  pointer-events: none;
}

.iosum-muestra-aviso.visible {
  opacity: 1;
  transform: translate(-50%, 0);
}

@media (prefers-reduced-motion: reduce) {
  .iosum-muestra-aviso { transition: none; }
}

/* En el teléfono la pestaña ocupa menos ancho para no pisar el margen del contenido. */
@media (max-width: 640px) {
  .iosum-muestra-sello { width: 18px; padding: 8px 0 2px; font-size: 10px; gap: 2px; }
  .iosum-muestra-sello button { width: 16px; height: 16px; font-size: 13px; }
}