/* Visor de montaje 3D (montaje-3d.html). Usa las variables de marca.css y style.css. */

body.m3d {
  padding: 0;
  --m3d-accent: var(--brand-terracotta);
  /* Texto secundario legible al sol (6:1 sobre blanco; el salvia de marca da 3,6:1) */
  --m3d-muted: #56655c;
  --m3d-panel-w: 400px;
  --m3d-bar-h: 56px;
  --m3d-gutter: 1.25rem;
  height: 100dvh;
  overflow: hidden;
  display: flex;
  flex-direction: column;
  background: var(--color-background);
}

/* El atributo hidden debe ganar a los display de los componentes */
body.m3d [hidden] {
  display: none !important;
}

/* Solo para lectores de pantalla */
.m3d-sr {
  position: absolute;
  width: 1px;
  height: 1px;
  margin: -1px;
  padding: 0;
  overflow: hidden;
  clip-path: inset(50%);
  white-space: nowrap;
  border: 0;
}

/* Barra superior */
.m3d-bar {
  flex: 0 0 var(--m3d-bar-h);
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 0.75rem;
  padding: 0 max(1rem, env(safe-area-inset-right)) 0 max(1rem, env(safe-area-inset-left));
  background: #fff;
  border-bottom: 1px solid var(--color-border);
}

.m3d-bar .toolbar-link {
  min-height: 40px;
  padding: 0.4rem 0.8rem;
}

.m3d-bar__title {
  display: flex;
  align-items: center;
  gap: 0.6rem;
  margin: 0;
  min-width: 0;
  font-family: var(--font-heading);
  font-weight: 700;
  font-size: 0.95rem;
  color: var(--color-brand-dark);
}

.m3d-bar__title img {
  height: 28px;
  width: auto;
}

.m3d-bar__title span {
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.m3d-bar__model {
  font-size: 0.85rem;
  color: var(--m3d-muted);
  white-space: nowrap;
}

/* Disposición */
.m3d-main {
  flex: 1 1 auto;
  min-height: 0;
  display: grid;
  grid-template-columns: minmax(0, 1fr) var(--m3d-panel-w);
}

.m3d-viewer {
  position: relative;
  min-height: 0;
  overflow: hidden;
  background: #f2efe7;
  touch-action: none;
}

.m3d-canvas {
  display: block;
  width: 100%;
  height: 100%;
  cursor: grab;
}

.m3d-canvas:active {
  cursor: grabbing;
}

/* Capas sobre el 3D */
.m3d-labels {
  position: absolute;
  inset: 0;
  pointer-events: none;
  overflow: hidden;
}

.m3d-label {
  position: absolute;
  top: 0;
  left: 0;
  min-width: 1.75rem;
  height: 1.75rem;
  padding: 0 0.4rem;
  display: grid;
  place-items: center;
  border-radius: 999px;
  background: var(--m3d-accent);
  color: #fff;
  font-family: var(--font-heading);
  font-weight: 700;
  font-size: 0.82rem;
  line-height: 1;
  box-shadow: 0 2px 6px rgb(0 0 0 / 0.28);
  border: 2px solid #fff;
  /* Se pueden tocar: enseñan el nombre de la pieza */
  pointer-events: auto;
  cursor: pointer;
  animation: m3d-label-entra 0.3s ease-out;
}

@keyframes m3d-label-entra {
  from { opacity: 0; }
}

/* Globo con el nombre de la pieza tocada (la posición la pone el JS) */
.m3d-pick {
  position: absolute;
  top: 0;
  left: 0;
  z-index: 3;
  width: max-content;
  max-width: min(280px, calc(100% - 16px));
  padding: 0.5rem 0.75rem;
  border-radius: 10px;
  background: rgba(var(--brand-ink-rgb), 0.94);
  color: #fff;
  font-size: 0.92rem;
  font-weight: 600;
  line-height: 1.3;
  box-shadow: 0 6px 18px rgb(0 0 0 / 0.22);
  pointer-events: none;
}

/* Aviso arriba del visor durante una acción (p. ej. la caja que se coge) */
.m3d-cartel {
  position: absolute;
  top: 1rem;
  left: 50%;
  z-index: 2;
  width: max-content;
  max-width: calc(100% - 2rem);
  transform: translateX(-50%);
  padding: 0.5rem 1.1rem;
  border-radius: 20px; /* redondeado también si ocupa dos líneas */
  background: var(--brand-forest);
  color: #fff;
  font-family: var(--font-heading);
  font-weight: 600;
  font-size: 1rem;
  line-height: 1.3;
  text-align: center;
  box-shadow: 0 4px 14px rgb(0 0 0 / 0.25);
  pointer-events: none;
  animation: m3d-cartel-entra 0.25s ease-out;
}

@keyframes m3d-cartel-entra {
  from { opacity: 0; transform: translate(-50%, -0.5rem); }
}

/* Con poco ancho arriba están «Vista general» y «Ver lo que falta»: el aviso va abajo */
@media (max-width: 700px) {
  .m3d-cartel {
    top: auto;
    bottom: 0.75rem;
    font-size: 0.95rem;
  }

  @keyframes m3d-cartel-entra {
    from { opacity: 0; transform: translate(-50%, 0.5rem); }
  }
}

body.m3d--grabar .m3d-cartel {
  visibility: hidden; /* en el vídeo se dibuja en la imagen */
}

/* Carga del modelo, con barra de progreso */
.m3d-loading {
  position: absolute;
  inset: 0;
  z-index: 4;
  margin: 0;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 0.9rem;
  padding: 2rem;
  text-align: center;
  font-family: var(--font-heading);
  font-weight: 600;
  color: var(--color-brand-dark);
  background: #f2efe7;
}

.m3d-loading__bar {
  display: block;
  width: min(220px, 60%);
  height: 6px;
  border-radius: 3px;
  background: rgba(var(--brand-forest-rgb), 0.12);
  overflow: hidden;
}

.m3d-loading__fill {
  display: block;
  height: 100%;
  border-radius: inherit;
  background: var(--color-brand);
  transform: scaleX(0.04);
  transform-origin: left;
  transition: transform 0.2s ease-out;
}

/* Sin tamaño conocido: la barra va y viene */
.m3d-loading__bar.is-indeterminada .m3d-loading__fill {
  width: 35%;
  transform: none;
  animation: m3d-carga 1.2s ease-in-out infinite;
}

@keyframes m3d-carga {
  from { margin-left: -35%; }
  to { margin-left: 100%; }
}

.m3d-loading.is-error {
  color: var(--brand-terracotta-hover);
}

.m3d-loading small {
  font-family: var(--font-body);
  font-weight: 400;
  font-size: 0.75rem;
  color: var(--m3d-muted);
}

.m3d-viewtools {
  position: absolute;
  top: 0.75rem;
  right: max(0.75rem, env(safe-area-inset-right));
  z-index: 2;
  display: flex;
  gap: 0.5rem;
}

.m3d-chip {
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
  min-height: 40px;
  font-family: var(--font-heading);
  font-size: 0.82rem;
  font-weight: 600;
  padding: 0.45rem 0.85rem;
  border-radius: 999px;
  border: 1px solid var(--color-border);
  background: rgb(255 255 255 / 0.94);
  color: var(--color-brand-dark);
  box-shadow: 0 1px 3px rgb(0 0 0 / 0.08);
  cursor: pointer;
  -webkit-tap-highlight-color: transparent;
}

.m3d-chip .m3d-icono {
  width: 1.05em;
  height: 1.05em;
}

.m3d-chip[aria-pressed="true"] {
  background: var(--color-brand);
  border-color: var(--color-brand);
  color: #fff;
}

.m3d-hint {
  position: absolute;
  left: 50%;
  bottom: 0.9rem;
  transform: translateX(-50%);
  margin: 0;
  padding: 0.45rem 0.9rem;
  border-radius: 999px;
  background: rgba(var(--brand-ink-rgb), 0.78);
  color: #fff;
  font-size: 0.82rem;
  white-space: nowrap;
  pointer-events: none;
  transition: opacity 0.4s;
}

.m3d-hint.is-hidden {
  opacity: 0;
}

.m3d-hint__corto {
  display: none;
}

/* Panel de pasos */
.m3d-panel {
  display: flex;
  flex-direction: column;
  min-height: 0;
  background: #fff;
  border-left: 1px solid var(--color-border);
}

.m3d-cabeza {
  flex: none;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 0.75rem;
  padding: 0.6rem var(--m3d-gutter) 0;
}

.m3d-fase-actual {
  min-width: 0;
  margin: 0;
  font-size: 0.82rem;
  line-height: 1.3;
  color: var(--m3d-muted);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.m3d-fase-actual strong {
  color: var(--color-text);
  font-weight: 600;
}

.m3d-pasos-btn {
  flex: none;
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
  min-height: 40px;
  margin-right: -0.6rem;
  padding: 0 0.6rem;
  border: 0;
  border-radius: 8px;
  background: none;
  color: var(--color-brand);
  font-family: var(--font-heading);
  font-size: 0.85rem;
  font-weight: 600;
  cursor: pointer;
  -webkit-tap-highlight-color: transparent;
}

/* Barra de fases: un segmento por fase, largo según sus pasos. El nombre de la
   fase actual va en la línea de arriba. */
.m3d-fases {
  flex: none;
  display: flex;
  gap: 4px;
  padding: 0.25rem var(--m3d-gutter) 0;
}

.m3d-fase {
  flex: 1 1 0;
  min-width: 20px;
  display: flex;
  align-items: center;
  height: 22px; /* zona táctil más alta que la barra */
  padding: 0;
  border: 0;
  background: none;
  cursor: pointer;
  -webkit-tap-highlight-color: transparent;
}

.m3d-fase__bar {
  display: block;
  width: 100%;
  height: 6px;
  border-radius: 3px;
  background: var(--color-border);
  overflow: hidden;
}

.m3d-fase__fill {
  display: block;
  height: 100%;
  background: var(--color-brand);
  transform: scaleX(0);
  transform-origin: left;
}

.m3d-fase__bar {
  transition: height 0.2s;
}

.m3d-fase.is-current .m3d-fase__bar {
  height: 9px;
  border-radius: 5px;
}

/* Texto del paso: si no cabe, se difumina abajo y sale «Desliza para leer más» */
.m3d-step-wrap {
  position: relative;
  flex: 1 1 auto;
  min-height: 0;
  display: flex;
  flex-direction: column;
}

.m3d-step {
  flex: 1 1 auto;
  min-height: 0;
  overflow-y: auto;
  overscroll-behavior: contain;
  padding: 0.75rem var(--m3d-gutter) 1rem;
}

.m3d-step.is-desborda {
  -webkit-mask-image: linear-gradient(#000 calc(100% - 3.5rem), transparent);
  mask-image: linear-gradient(#000 calc(100% - 3.5rem), transparent);
}

.m3d-step:focus-visible {
  outline: 3px solid var(--brand-forest);
  outline-offset: -3px;
}

.m3d-mas {
  position: absolute;
  right: var(--m3d-gutter);
  bottom: 0.5rem;
  display: inline-flex;
  align-items: center;
  gap: 0.3rem;
  min-height: 34px;
  padding: 0 0.85rem;
  border: 1px solid var(--color-border);
  border-radius: 999px;
  background: #fff;
  color: var(--color-brand-dark);
  font-family: var(--font-heading);
  font-size: 0.8rem;
  font-weight: 600;
  white-space: nowrap;
  box-shadow: 0 3px 10px rgb(0 0 0 / 0.12);
  cursor: pointer;
  animation: m3d-mas-entra 0.3s ease-out;
}

@keyframes m3d-mas-entra {
  from { opacity: 0; transform: translateY(0.4rem); }
}

.m3d-step__num {
  margin: 0 0 0.25rem;
  font-size: 0.8rem;
  font-weight: 600;
  letter-spacing: 0.04em;
  text-transform: uppercase;
  color: var(--color-brand);
}

.m3d-step__title {
  margin: 0 0 0.6rem;
  font-family: var(--font-heading);
  font-size: 1.35rem;
  line-height: 1.25;
  color: var(--color-text);
  text-wrap: balance;
}

.m3d-step__text {
  margin: 0 0 0.9rem;
  font-size: 1.02rem;
  line-height: 1.55;
  color: var(--color-text);
}

.m3d-box {
  margin: 0 0 0.9rem;
  padding: 0.65rem 0.8rem;
  border-radius: 8px;
  font-size: 0.95rem;
  line-height: 1.45;
}

.m3d-box--consejo {
  background: var(--brand-leaf-tint);
  border-left: 4px solid var(--color-brand);
}

.m3d-box--consejo::before {
  content: "Consejo: ";
  font-weight: 700;
}

.m3d-box--aviso {
  background: var(--brand-terracotta-tint);
  border-left: 4px solid var(--color-warning);
}

.m3d-box--aviso::before {
  content: "Atención: ";
  font-weight: 700;
  color: var(--brand-terracotta-hover);
}

/* Piezas del paso: fila de fichas bajo el título (número, nombre y cantidad) */
.m3d-piezas {
  list-style: none;
  margin: 0 0 0.75rem;
  padding: 0;
  display: flex;
  flex-wrap: wrap;
  gap: 0.4rem;
}

.m3d-pieza {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  max-width: 100%;
  min-height: 34px;
  padding: 0.2rem 0.65rem 0.2rem 0.25rem;
  border: 1px solid var(--color-border);
  border-radius: 999px;
  background: var(--brand-sand);
  font-size: 0.86rem;
  line-height: 1.2;
}

.m3d-pieza--sin-num {
  padding-left: 0.65rem;
}

.m3d-pieza__num {
  flex: 0 0 auto;
  min-width: 1.6rem;
  height: 1.6rem;
  padding: 0 0.3rem;
  display: grid;
  place-items: center;
  border-radius: 999px;
  background: var(--m3d-accent);
  color: #fff;
  font-family: var(--font-heading);
  font-weight: 700;
  font-size: 0.78rem;
}

.m3d-pieza__name {
  min-width: 0;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
  color: var(--color-text);
}

.m3d-pieza__qty {
  flex: none;
  font-weight: 700;
  color: var(--brand-forest);
}

/* Tarjeta final: montaje terminado */
.m3d-fin {
  display: grid;
  gap: 0.7rem;
}

.m3d-fin__check {
  display: none;
  flex: none;
  width: 1.6em;
  height: 1.6em;
  color: var(--color-brand);
}

.m3d--terminado .m3d-step__title {
  display: flex;
  align-items: center;
  gap: 0.55rem;
}

.m3d--terminado .m3d-fin__check {
  display: block;
}

.m3d-fin__check circle {
  stroke-dasharray: 151;
  animation: m3d-fin-circulo 0.6s ease-out both;
}

.m3d-fin__check path {
  stroke-dasharray: 36;
  animation: m3d-fin-marca 0.35s 0.45s ease-out both;
}

@keyframes m3d-fin-circulo {
  from { stroke-dashoffset: 151; }
}

@keyframes m3d-fin-marca {
  from { stroke-dashoffset: 36; }
}

.m3d-fin__texto {
  margin: 0;
  font-size: 0.97rem;
  line-height: 1.5;
  color: var(--m3d-muted);
}

.m3d-fin .m3d-btn {
  width: 100%;
  text-decoration: none;
}

/* Al terminar, el botón de abajo («Repetir todo») pasa a secundario */
.m3d--terminado .m3d-controls .m3d-btn--primary {
  background: #fff;
  border-color: var(--color-border);
  color: var(--color-brand-dark);
}

/* Hoja con todos los pasos (diálogo) */
.m3d-hoja {
  width: min(440px, calc(100vw - 2rem));
  max-height: min(80dvh, 720px);
  margin: auto;
  padding: 0;
  border: 0;
  border-radius: 16px;
  background: #fff;
  color: var(--color-text);
  box-shadow: 0 20px 60px rgb(0 0 0 / 0.3);
  overflow: hidden;
}

.m3d-hoja[open] {
  display: flex;
  flex-direction: column;
  animation: m3d-hoja-entra 0.22s ease-out;
}

.m3d-hoja::backdrop {
  background: rgba(var(--brand-ink-rgb), 0.45);
}

@keyframes m3d-hoja-entra {
  from { opacity: 0; transform: translateY(12px); }
}

.m3d-hoja__cabeza {
  flex: none;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  padding: 0.75rem 0.75rem 0.75rem 1.25rem;
  border-bottom: 1px solid var(--color-border);
}

.m3d-hoja__titulo {
  margin: 0;
  font-size: 1.1rem;
  color: var(--color-text);
}

.m3d-hoja__cerrar {
  display: grid;
  place-items: center;
  width: 44px;
  height: 44px;
  border: 0;
  border-radius: 999px;
  background: var(--brand-sand);
  color: var(--color-text);
  cursor: pointer;
}

.m3d-hoja__cerrar .m3d-icono {
  width: 1.3em;
  height: 1.3em;
}

.m3d-hoja__cuerpo {
  flex: 1 1 auto;
  min-height: 0;
  overflow-y: auto;
  overscroll-behavior: contain;
  padding: 0.25rem 0 max(0.75rem, env(safe-area-inset-bottom));
}

.m3d-hoja__fase {
  margin: 0;
  padding: 0.9rem 1.25rem 0.35rem;
  font-family: var(--font-heading);
  font-size: 0.75rem;
  font-weight: 600;
  letter-spacing: 0.05em;
  text-transform: uppercase;
  color: var(--m3d-muted);
}

.m3d-hoja ol {
  list-style: none;
  margin: 0;
  padding: 0;
}

.m3d-hoja li button {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  width: 100%;
  min-height: 48px;
  padding: 0.4rem 1.25rem;
  border: 0;
  background: none;
  font: inherit;
  font-size: 0.97rem;
  line-height: 1.3;
  color: var(--color-text);
  text-align: left;
  cursor: pointer;
}

.m3d-hoja__n {
  flex: none;
  display: grid;
  place-items: center;
  width: 1.85rem;
  height: 1.85rem;
  border-radius: 999px;
  border: 1.5px solid var(--color-border);
  font-family: var(--font-heading);
  font-size: 0.8rem;
  font-weight: 600;
  color: var(--m3d-muted);
}

.m3d-hoja li.is-done .m3d-hoja__n {
  border-color: var(--color-brand);
  background: var(--brand-leaf-tint);
  color: var(--color-brand);
}

.m3d-hoja li.is-current button {
  background: var(--brand-leaf-tint);
  font-weight: 600;
}

.m3d-hoja li.is-current .m3d-hoja__n {
  border-color: var(--color-brand);
  background: var(--color-brand);
  color: #fff;
}

/* Controles */
.m3d-controls {
  flex: none;
  padding: 0.6rem var(--m3d-gutter) max(0.8rem, env(safe-area-inset-bottom));
  border-top: 1px solid var(--color-border);
  background: #fff;
}

.m3d-linea {
  display: block;
  width: 100%;
  height: 24px;
  margin: 0 0 0.45rem;
  accent-color: var(--color-brand);
}

.m3d-buttons {
  display: flex;
  gap: 0.5rem;
}

.m3d-btn {
  flex: 1 1 auto;
  min-height: 48px;
  padding: 0 0.9rem;
  border-radius: 10px;
  border: 1px solid var(--color-border);
  background: #fff;
  color: var(--color-brand-dark);
  font-family: var(--font-heading);
  font-weight: 600;
  font-size: 0.97rem;
  white-space: nowrap;
  cursor: pointer;
  -webkit-tap-highlight-color: transparent;
  transition: background-color 0.15s, border-color 0.15s, transform 0.1s;
}

.m3d-btn:active:not(:disabled) {
  transform: scale(0.97);
}

.m3d-btn--icon {
  flex: 0 0 48px;
  padding: 0;
  font-size: 1.1rem;
}

.m3d-btn--primary {
  flex-grow: 2;
  background: var(--color-brand);
  border-color: var(--color-brand);
  color: #fff;
}

/* :hover solo con ratón (en el móvil se queda pegado tras tocar) */
@media (hover: hover) {
  .m3d-btn:hover:not(:disabled),
  .m3d-chip:hover,
  .m3d-pasos-btn:hover {
    border-color: var(--color-brand);
  }

  .m3d-pasos-btn:hover,
  .m3d-hoja li button:hover {
    background: var(--brand-leaf-tint);
  }

  .m3d-btn--primary:hover:not(:disabled) {
    background: var(--color-brand-dark);
    border-color: var(--color-brand-dark);
  }

  .m3d-btn--primary.is-listo:hover:not(:disabled) {
    background: var(--brand-terracotta-hover);
    border-color: var(--brand-terracotta-hover);
  }
}

/* Foco visible con teclado en todos los controles */
.m3d-btn:focus-visible,
.m3d-chip:focus-visible,
.m3d-pasos-btn:focus-visible,
.m3d-fase:focus-visible,
.m3d-hoja button:focus-visible,
.m3d-linea:focus-visible,
.m3d-bar .toolbar-link:focus-visible {
  outline: 3px solid var(--brand-forest);
  outline-offset: 2px;
}

.m3d-btn--primary:focus-visible {
  box-shadow: 0 0 0 2px #fff inset;
}

/* Mientras se anima el paso, «Siguiente» lleva una barra fina abajo que se va
   llenando (--progreso, de 0 a 1); al terminar se pone en teja y late: ya se
   puede pasar al siguiente. */
.m3d-btn--primary {
  position: relative;
  overflow: hidden;
  isolation: isolate;
}

.m3d-btn--primary::before {
  content: "";
  position: absolute;
  inset: auto 0 0 0;
  height: 4px;
  background: rgb(255 255 255 / 0.8);
  transform: scaleX(var(--progreso, 0));
  transform-origin: left;
}

.m3d-btn--primary.is-listo,
.m3d-btn--primary.is-listo:focus-visible {
  overflow: visible;
  background: var(--brand-terracotta);
  border-color: var(--brand-terracotta);
  animation: m3d-listo 1.3s ease-out 3;
}

.m3d-btn--primary.is-listo::before {
  content: none;
}

@keyframes m3d-listo {
  0% { box-shadow: 0 0 0 0 rgba(192, 96, 58, 0.55); }
  100% { box-shadow: 0 0 0 14px rgba(192, 96, 58, 0); }
}

.m3d-btn:disabled {
  opacity: 0.4;
  cursor: default;
}

.m3d-btn[aria-pressed="true"] {
  background: var(--brand-leaf-tint);
  border-color: var(--color-brand);
}

.m3d-noscript {
  padding: 1rem;
  text-align: center;
}

/* Móvil y tablet en vertical: 3D arriba, panel abajo */
@media (max-width: 860px) {
  body.m3d {
    --m3d-bar-h: 50px;
    --m3d-gutter: 1rem;
  }

  .m3d-main {
    grid-template-columns: minmax(0, 1fr);
    grid-template-rows: minmax(0, 48fr) minmax(0, 52fr);
  }

  .m3d-panel {
    border-left: 0;
    border-top: 1px solid var(--color-border);
  }

  .m3d-bar__model,
  .m3d-bar__title img {
    display: none;
  }

  .m3d-step__title {
    font-size: 1.18rem;
  }

  /* Fichas de piezas en una sola fila que se desliza de lado: el texto del paso
     queda a la vista */
  .m3d-piezas {
    flex-wrap: nowrap;
    overflow-x: auto;
    margin-left: calc(-1 * var(--m3d-gutter));
    margin-right: calc(-1 * var(--m3d-gutter));
    padding: 0 var(--m3d-gutter) 2px;
    scrollbar-width: none;
    overscroll-behavior-x: contain;
    -webkit-mask-image: linear-gradient(90deg, transparent, #000 var(--m3d-gutter), #000 calc(100% - 2rem), transparent);
    mask-image: linear-gradient(90deg, transparent, #000 var(--m3d-gutter), #000 calc(100% - 2rem), transparent);
  }

  .m3d-piezas::-webkit-scrollbar {
    display: none;
  }

  .m3d-pieza {
    flex: none;
  }

  .m3d-pieza__name {
    max-width: 13em;
  }

  .m3d-step__text {
    font-size: 1rem;
  }

  /* «Anterior» solo con icono: el botón principal tiene sitio */
  .m3d-btn--prev {
    flex: 0 0 48px;
    padding: 0;
  }

  .m3d-btn--prev .m3d-btn__txt {
    position: absolute;
    width: 1px;
    height: 1px;
    overflow: hidden;
    clip-path: inset(50%);
  }

  .m3d-btn--prev .m3d-icono {
    width: 1.3em;
    height: 1.3em;
  }

  .m3d-hint__largo {
    display: none;
  }

  .m3d-hint__corto {
    display: inline;
  }

  /* Los números de pieza en el móvil, algo más pequeños */
  .m3d-label {
    min-width: 1.6rem;
    height: 1.6rem;
    font-size: 0.78rem;
  }

  /* La hoja de pasos sale desde abajo */
  .m3d-hoja {
    width: 100%;
    max-width: none;
    max-height: 78dvh;
    margin: auto 0 0;
    border-radius: 18px 18px 0 0;
  }

  .m3d-hoja__cabeza::before {
    content: "";
    position: absolute;
    top: 6px;
    left: 50%;
    width: 40px;
    height: 4px;
    margin-left: -20px;
    border-radius: 2px;
    background: var(--color-border);
  }

  .m3d-hoja__cabeza {
    position: relative;
  }

  @keyframes m3d-hoja-entra {
    from { transform: translateY(100%); }
  }
}

/* Pantallas bajas (360×740 y similares): algo más de sitio para el texto */
@media (max-width: 860px) and (max-height: 760px) {
  .m3d-main {
    grid-template-rows: minmax(0, 43fr) minmax(0, 57fr);
  }

  .m3d-chip {
    min-height: 36px;
    padding: 0.35rem 0.7rem;
  }
}

/* Muy estrecho: el chip «Vista general» se queda en icono */
@media (max-width: 380px) {
  .m3d-viewtools {
    gap: 0.4rem;
  }

  #m3d-general {
    width: 40px;
    padding: 0;
    justify-content: center;
    font-size: 0;
  }

  #m3d-general .m3d-icono {
    width: 18px;
    height: 18px;
  }
}

/* Móvil en horizontal: 3D a la izquierda y panel a la derecha, con los
   controles siempre a la vista */
@media (max-width: 960px) and (orientation: landscape) and (max-height: 520px) {
  body.m3d {
    --m3d-bar-h: 44px;
    --m3d-gutter: 0.9rem;
  }

  .m3d-main {
    grid-template-columns: minmax(0, 1fr) minmax(300px, 42%);
    grid-template-rows: minmax(0, 1fr);
  }

  .m3d-panel {
    border-top: 0;
    border-left: 1px solid var(--color-border);
    padding-right: env(safe-area-inset-right);
  }

  .m3d-bar__title img {
    display: none;
  }

  .m3d-cabeza {
    padding-top: 0.35rem;
  }

  .m3d-step {
    padding-top: 0.4rem;
  }

  .m3d-step__title {
    font-size: 1.08rem;
    margin-bottom: 0.4rem;
  }

  .m3d-controls {
    padding-top: 0.45rem;
    padding-bottom: max(0.5rem, env(safe-area-inset-bottom));
  }

  /* Sin deslizador: la barra de fases ya enseña el avance y lleva a cada fase */
  .m3d-linea {
    display: none;
  }

  .m3d-btn {
    min-height: 44px;
  }

  .m3d-btn--icon,
  .m3d-btn--prev {
    flex-basis: 44px;
  }

  .m3d-cartel {
    top: 3.6rem;
    bottom: auto;
    font-size: 0.9rem;
  }

  .m3d-hoja {
    width: min(440px, calc(100vw - 2rem));
    max-height: 90dvh;
    margin: auto;
    border-radius: 16px;
  }

  .m3d-hoja__cabeza::before {
    content: none;
  }
}

@media (prefers-reduced-motion: reduce) {
  .m3d-hint,
  .m3d-btn,
  .m3d-loading__fill {
    transition: none;
  }

  .m3d-btn--primary.is-listo,
  .m3d-cartel,
  .m3d-label,
  .m3d-mas,
  .m3d-hoja[open],
  .m3d-fin__check circle,
  .m3d-fin__check path {
    animation: none;
  }

  .m3d-btn:active:not(:disabled) {
    transform: none;
  }
}

/* Pasos en texto cuando el 3D no puede arrancar */
.m3d-texto {
  margin: 0.5rem 0 0;
  padding-left: 1.4rem;
}

.m3d-texto li {
  margin-bottom: 1.1rem;
}

.m3d-texto h2 {
  margin: 0 0 0.3rem;
  font-size: 1.05rem;
}

.m3d-texto p {
  margin: 0 0 0.5rem;
  line-height: 1.5;
}

/* Sin 3D: el aviso ocupa poco y el texto de los pasos tiene todo el sitio */
body.m3d--sin3d .m3d-main {
  grid-template-rows: auto minmax(0, 1fr);
  grid-template-columns: minmax(0, 1fr);
}

body.m3d--sin3d .m3d-viewer {
  min-height: 0;
}

body.m3d--sin3d .m3d-loading {
  position: static;
  padding: 1.25rem 1rem;
}

/* Iconos SVG de los botones */
.m3d-icono {
  width: 1.15em;
  height: 1.15em;
  flex: 0 0 auto;
}

.m3d-btn,
.m3d-bar .toolbar-link {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.4rem;
}

.m3d-btn--icon .m3d-icono {
  width: 1.3em;
  height: 1.3em;
}

/* Modo grabación (?grabar): solo el 3D, a pantalla completa */
body.m3d--grabar .m3d-bar,
body.m3d--grabar .m3d-panel,
body.m3d--grabar .m3d-viewtools,
body.m3d--grabar .m3d-hint,
body.m3d--grabar .m3d-labels {
  display: none !important;
}

body.m3d--grabar .m3d-main {
  grid-template-columns: minmax(0, 1fr);
  grid-template-rows: minmax(0, 1fr) 74px; /* abajo, hueco para el rótulo del vídeo */
}