/* Barra de navegación siempre disponible durante la lectura. */
.topbar {
  position: sticky;
  top: 0;
  z-index: 30;
}

/* Cada vista muestra únicamente su propio índice. */
.side-nav nav[hidden] {
  display: none !important;
}

/* Galería ampliable. */
.wide img, .gallery img {
  cursor: zoom-in;
}

.image-lightbox {
  position: fixed;
  inset: 0;
  z-index: 60;
  display: grid;
  place-items: center;
  padding: clamp(18px, 4vw, 52px);
  background: rgba(5, 20, 25, .94);
  overflow: hidden;
}

.image-lightbox[hidden] { display: none !important; }

.image-lightbox img {
  display: block;
  max-width: calc(100vw - 72px);
  max-height: calc(100vh - 96px);
  width: auto;
  height: auto;
  object-fit: contain;
  box-shadow: 0 16px 56px rgba(0, 0, 0, .48);
}

.image-lightbox button {
  position: absolute;
  top: 12px;
  right: 14px;
  width: 42px;
  height: 42px;
  border: 1px solid rgba(255, 255, 255, .65);
  border-radius: 50%;
  background: rgba(10, 37, 46, .88);
  color: #fff;
  cursor: pointer;
  font: 30px/1 Arial, sans-serif;
}

.compare-close {
  max-width: 1120px;
  margin: 25px 0 0;
  color: #dcebea;
  font-size: 18px;
}

@media (min-width: 769px) {
  .side-nav { top: 58px; }
}