/* ==========================================================================
   Forprocer LMS - Visor de Leccion
   Layout full-height con header sticky, contenido scrollable y footer fijo.
   Incluye modal de countdown, barra de progreso y navegacion entre lecciones.
   ========================================================================== */

/* --------------------------------------------------------------------------
   Layout principal del visor (sidebar + main)
   -------------------------------------------------------------------------- */
.viewer-layout {
  min-height: 100vh;
  background: var(--color-white);
}

/* Wrapper del contenido principal (header + content + footer) */
.viewer-layout__main {
  display: flex;
  flex-direction: column;
  min-height: 100vh;
  transition: margin-left 0.3s ease;
}

.viewer-layout.sidebar-abierta .viewer-layout__main {
  margin-left: 320px;
}

/* --------------------------------------------------------------------------
   Header: Barra superior (curso/convocatoria) + breadcrumb + boton volver
   -------------------------------------------------------------------------- */
.viewer-header {
  display: flex;
  flex-direction: column;
  padding: var(--space-2) var(--space-6) var(--space-3);
  background: var(--glass-bg-card);
  backdrop-filter: blur(var(--glass-blur));
  -webkit-backdrop-filter: blur(var(--glass-blur));
  border-bottom: 1px solid var(--glass-border);
  flex-shrink: 0;
  z-index: var(--z-sticky);
  position: sticky;
  top: 0;
}

/* Fila superior: nombre curso + convocatoria + progreso global */
.viewer-header__top {
  display: flex;
  align-items: center;
  gap: var(--space-2);
  padding-bottom: var(--space-2);
  margin-bottom: var(--space-2);
  border-bottom: 1px solid var(--color-gray-100);
  font-size: var(--text-xs);
  color: var(--color-gray-500);
  min-width: 0;
}

.viewer-header__curso-nombre {
  font-weight: var(--font-semibold);
  color: var(--color-gray-700);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.viewer-header__separador {
  color: var(--color-gray-300);
  flex-shrink: 0;
}

.viewer-header__conv-nombre {
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.viewer-header__curso-progreso {
  display: flex;
  align-items: center;
  gap: var(--space-2);
  margin-left: auto;
  flex-shrink: 0;
}

.viewer-header__curso-progreso-text {
  font-weight: var(--font-semibold);
  color: var(--color-primary);
  font-size: var(--text-xs);
}

.viewer-header__curso-progreso-bar {
  width: 80px;
  height: 4px;
  background: var(--color-gray-200);
  border-radius: var(--radius-full);
  overflow: hidden;
}

.viewer-header__curso-progreso-fill {
  height: 100%;
  background: var(--color-primary);
  border-radius: var(--radius-full);
  transition: width 0.3s ease;
}

/* Menu tres puntos */
.viewer-header__menu {
  position: relative;
  margin-left: var(--space-3);
  flex-shrink: 0;
}

.viewer-header__menu-btn {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 36px;
  height: 28px;
  border: none;
  background: none;
  color: var(--color-gray-400);
  border-radius: var(--radius-md);
  cursor: pointer;
  transition: color 0.15s ease, background 0.15s ease;
}

.viewer-header__menu-btn:hover {
  color: var(--color-primary);
  background: var(--color-gray-100);
}

.viewer-header__dropdown {
  display: none;
  position: absolute;
  top: calc(100% + 6px);
  right: 0;
  min-width: 160px;
  background: var(--color-white, #fff);
  border: 1px solid var(--color-gray-200);
  border-radius: var(--radius-lg);
  box-shadow: 0 8px 24px rgba(0, 0, 0, 0.1);
  padding: var(--space-1);
  z-index: var(--z-dropdown, 100);
}

.viewer-header__dropdown.is-open {
  display: block;
}

.viewer-header__dropdown-item {
  display: flex;
  align-items: center;
  gap: var(--space-2);
  padding: var(--space-2) var(--space-3);
  font-size: var(--text-sm);
  font-weight: var(--font-medium);
  color: var(--color-gray-700);
  text-decoration: none;
  border-radius: var(--radius-md);
  transition: background 0.12s ease, color 0.12s ease;
}

.viewer-header__dropdown-item:hover {
  background: var(--color-gray-100);
  color: var(--color-primary);
  text-decoration: none;
}

.viewer-header__dropdown-item svg {
  width: 16px;
  height: 16px;
  flex-shrink: 0;
}

/* Fila principal: toggle sidebar + boton volver + breadcrumb + timer */
.viewer-header__main {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  min-height: 36px;
}

/* Boton toggle sidebar */
.viewer-header__sidebar-toggle {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 36px;
  height: 36px;
  border-radius: var(--radius-md);
  color: var(--color-gray-600);
  background: none;
  border: none;
  cursor: pointer;
  flex-shrink: 0;
  transition: background-color var(--transition-fast), color var(--transition-fast);
}

.viewer-header__sidebar-toggle:hover {
  background: var(--color-gray-100);
  color: var(--color-gray-900);
}

/* Boton de volver al portal */
.viewer-header__back {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 36px;
  height: 36px;
  border-radius: var(--radius-md);
  color: var(--color-gray-600);
  cursor: pointer;
  flex-shrink: 0;
  transition: background-color var(--transition-fast), color var(--transition-fast);
}

.viewer-header__back:hover {
  background: var(--color-gray-100);
  color: var(--color-gray-900);
}

.viewer-header__back svg {
  width: 20px;
  height: 20px;
}

/* Breadcrumb de navegacion (curso > modulo > leccion) */
.viewer-header__breadcrumb {
  display: flex;
  align-items: center;
  gap: var(--space-2);
  font-size: var(--text-sm);
  color: var(--color-gray-500);
  min-width: 0;
  flex: 1;
  overflow: hidden;
}

.viewer-header__breadcrumb a {
  color: var(--color-gray-500);
  text-decoration: none;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
  transition: color var(--transition-fast);
}

.viewer-header__breadcrumb a:hover {
  color: var(--color-primary);
  text-decoration: none;
}

/* Separador del breadcrumb (icono chevron) */
.viewer-header__breadcrumb-sep {
  color: var(--color-gray-300);
  flex-shrink: 0;
}

.viewer-header__breadcrumb-sep svg {
  width: 16px;
  height: 16px;
}

/* Nombre de la leccion actual (resaltado) */
.viewer-header__leccion-nombre {
  font-weight: var(--font-semibold);
  color: var(--color-gray-900);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

/* --------------------------------------------------------------------------
   Contenido principal del visor (area scrollable)
   -------------------------------------------------------------------------- */
.viewer-content {
  flex: 1;
  overflow-y: auto;
  padding: var(--space-6);
  display: flex;
  flex-direction: column;
}

/* --- Variante: Contenido HTML (lectura de texto enriquecido) --- */
.viewer-content--html {
  max-width: 100%;
  width: 100%;
  margin: 0;
  padding: var(--space-8) 10vw;
  align-self: stretch;
}

.viewer-content--html .fp-leccion {
  max-width: none;
  margin: 0;
}

.viewer-content--html h1,
.viewer-content--html h2,
.viewer-content--html h3,
.viewer-content--html h4,
.viewer-content--html h5,
.viewer-content--html h6 {
  color: var(--color-gray-900);
  margin-top: var(--space-6);
  margin-bottom: var(--space-3);
}

.viewer-content--html h1:first-child,
.viewer-content--html h2:first-child,
.viewer-content--html h3:first-child {
  margin-top: 0;
}

.viewer-content--html p {
  font-size: var(--text-base);
  line-height: var(--leading-relaxed);
  color: var(--color-gray-700);
  margin-bottom: var(--space-4);
}

.viewer-content--html img {
  max-width: 100%;
  border-radius: var(--radius-lg);
  margin: var(--space-4) 0;
  box-shadow: var(--shadow-sm);
}

.viewer-content--html a {
  color: var(--color-primary);
  text-decoration: underline;
  transition: color var(--transition-fast);
}

.viewer-content--html a:hover {
  color: var(--color-primary-dark);
}

.viewer-content--html ul,
.viewer-content--html ol {
  margin-bottom: var(--space-4);
  padding-left: var(--space-6);
}

.viewer-content--html li {
  margin-bottom: var(--space-2);
  line-height: var(--leading-relaxed);
  color: var(--color-gray-700);
}

.viewer-content--html blockquote {
  border-left: 4px solid var(--color-primary-200);
  padding: var(--space-3) var(--space-4);
  margin: var(--space-4) 0;
  background: var(--color-primary-50);
  border-radius: 0 var(--radius-md) var(--radius-md) 0;
  color: var(--color-gray-700);
}

.viewer-content--html pre {
  background: var(--color-gray-900);
  color: var(--color-gray-100);
  padding: var(--space-4);
  border-radius: var(--radius-lg);
  overflow-x: auto;
  margin: var(--space-4) 0;
  font-family: var(--font-family-mono);
  font-size: var(--text-sm);
  line-height: var(--leading-normal);
}

.viewer-content--html table {
  width: 100%;
  border-collapse: collapse;
  margin: var(--space-4) 0;
  font-size: var(--text-sm);
}

.viewer-content--html th,
.viewer-content--html td {
  padding: var(--space-3) var(--space-4);
  border: 1px solid var(--color-gray-200);
  text-align: left;
}

.viewer-content--html th {
  background: var(--color-gray-50);
  font-weight: var(--font-semibold);
  color: var(--color-gray-700);
}

/* --- Variante: Video (aspect ratio 16:9) --- */
.viewer-content--video {
  padding: var(--space-4);
  max-width: 1200px;
  width: 100%;
  margin: 0 auto;
}

.viewer-content--video .video-container {
  position: relative;
  width: 100%;
  padding-top: 56.25%; /* Ratio 16:9 */
  background: var(--color-gray-900);
  border-radius: var(--glass-radius);
  overflow: hidden;
  box-shadow: var(--glass-shadow-lg);
}

.viewer-content--video .video-container iframe,
.viewer-content--video .video-container video {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  border: none;
}

/* --- Variante: PDF (embebido a pantalla completa) --- */
.viewer-content--pdf {
  padding: 0;
  flex: 1;
  display: flex;
}

.viewer-content--pdf embed,
.viewer-content--pdf iframe,
.viewer-content--pdf object {
  flex: 1;
  width: 100%;
  height: 100%;
  min-height: calc(100vh - 56px - 64px); /* header + footer */
  border: none;
}

/* --- Estado: Sin contenido disponible --- */
.viewer-sin-contenido {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  height: 100%;
  min-height: 300px;
  text-align: center;
  color: var(--color-gray-500);
  gap: var(--space-3);
}

.viewer-sin-contenido svg {
  width: 48px;
  height: 48px;
  color: var(--color-gray-300);
}

.viewer-sin-contenido__title {
  font-size: var(--text-lg);
  font-weight: var(--font-semibold);
  color: var(--color-gray-600);
}

.viewer-sin-contenido__text {
  font-size: var(--text-sm);
  color: var(--color-gray-400);
  max-width: 360px;
}

/* --------------------------------------------------------------------------
   Footer fijo: Navegacion + estado + progreso + boton completar
   -------------------------------------------------------------------------- */
.viewer-footer {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-3);
  padding: var(--space-3) var(--space-6);
  background: var(--glass-bg-card);
  backdrop-filter: blur(var(--glass-blur-strong));
  -webkit-backdrop-filter: blur(var(--glass-blur-strong));
  border-top: 1px solid var(--glass-border-strong);
  box-shadow: 0 -4px 16px rgba(0, 0, 0, 0.06);
  min-height: 64px;
  flex-shrink: 0;
  z-index: var(--z-sticky);
}

/* Navegacion: Anterior / Siguiente */
.viewer-footer__nav {
  display: flex;
  align-items: center;
  gap: var(--space-2);
  min-width: 0;
  flex-shrink: 0;
}

.viewer-footer__nav-btn {
  display: inline-flex;
  align-items: center;
  gap: var(--space-2);
  padding: var(--space-2) var(--space-4);
  font-size: var(--text-sm);
  font-weight: var(--font-medium);
  font-family: var(--font-family);
  color: var(--color-gray-700);
  background: var(--color-white);
  border: 1px solid var(--color-gray-300);
  border-radius: var(--radius-full);
  cursor: pointer;
  text-decoration: none;
  transition:
    background-color var(--transition-fast),
    border-color var(--transition-fast),
    color var(--transition-fast),
    box-shadow var(--transition-fast);
  min-height: 40px;
  max-width: 200px;
}

.viewer-footer__nav-btn span {
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.viewer-footer__nav-btn:hover {
  background: var(--color-gray-50);
  border-color: var(--color-gray-400);
  color: var(--color-gray-900);
}

.viewer-footer__nav-btn:disabled {
  opacity: 0.4;
  cursor: not-allowed;
  pointer-events: none;
}

.viewer-footer__nav-btn svg {
  width: 16px;
  height: 16px;
  flex-shrink: 0;
}

/* Indicador de estado del temporizador (dot + texto) - usado en header */
.viewer-footer__status {
  display: flex;
  align-items: center;
  gap: var(--space-2);
  font-size: var(--text-sm);
  color: var(--color-gray-500);
  white-space: nowrap;
  flex-shrink: 0;
}

.viewer-footer__status-dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  flex-shrink: 0;
}

/* Dot verde pulsante: temporizador activo */
.viewer-footer__status-dot--activo {
  background: var(--color-success);
  box-shadow: 0 0 6px rgba(var(--color-success-rgb), 0.5);
  animation: viewerStatusPulse 2s ease-in-out infinite;
}

/* Dot amarillo: temporizador pausado */
.viewer-footer__status-dot--pausado {
  background: var(--color-warning);
}

@keyframes viewerStatusPulse {
  0%, 100% { opacity: 1; }
  50% { opacity: 0.5; }
}

/* Bloque central del footer: porcentaje + tiempo + curso */
.viewer-footer__center {
  display: flex;
  align-items: center;
  gap: var(--space-2);
  font-size: var(--text-sm);
  color: var(--color-gray-500);
  white-space: nowrap;
  flex: 1;
  justify-content: center;
}

.viewer-footer__leccion-pct {
  font-weight: var(--font-semibold);
  color: var(--color-primary);
}

.viewer-footer__sep {
  color: var(--color-gray-300);
}

/* --------------------------------------------------------------------------
   Boton de completar leccion (destacado con gradiente)
   -------------------------------------------------------------------------- */
.viewer-completar-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-2);
  padding: var(--space-2) var(--space-5);
  min-height: 40px;
  font-family: var(--font-family);
  font-size: var(--text-sm);
  font-weight: var(--font-semibold);
  line-height: 1;
  color: var(--color-white);
  background: linear-gradient(135deg, var(--color-primary) 0%, var(--color-primary-light) 100%);
  border: none;
  border-radius: var(--radius-full);
  cursor: pointer;
  box-shadow: 0 2px 8px rgba(var(--color-primary-rgb), 0.3);
  white-space: nowrap;
  flex-shrink: 0;
  transition:
    background var(--transition-base),
    box-shadow var(--transition-base),
    transform var(--transition-base),
    opacity var(--transition-base);
}

.viewer-completar-btn:hover {
  background: linear-gradient(135deg, var(--color-primary-light) 0%, var(--color-primary-lighter, #6ec6d0) 100%);
  box-shadow: 0 4px 16px rgba(var(--color-primary-rgb), 0.4);
  transform: scale(1.02);
}

.viewer-completar-btn:active {
  transform: scale(0.98);
  box-shadow: 0 1px 4px rgba(var(--color-primary-rgb), 0.3);
}

/* Deshabilitado: gris y sin interaccion */
.viewer-completar-btn:disabled {
  opacity: 0.4;
  cursor: not-allowed;
  pointer-events: none;
  transform: none;
  box-shadow: none;
  background: var(--color-gray-300);
  color: var(--color-gray-500);
}

/* Habilitado: animacion de pulso para llamar la atencion */
.viewer-completar-btn:not(:disabled):not(.is-completed) {
  animation: viewerPulseGlow 2s ease-in-out infinite;
}

@keyframes viewerPulseGlow {
  0%, 100% { box-shadow: 0 0 0 0 rgba(var(--color-primary-rgb), 0.4); }
  50% { box-shadow: 0 0 0 8px rgba(var(--color-primary-rgb), 0); }
}

.viewer-completar-btn svg {
  width: 18px;
  height: 18px;
}

/* Estado completado: boton verde sin interaccion */
.viewer-completar-btn.is-completed {
  background: var(--color-success);
  box-shadow: 0 2px 8px rgba(var(--color-success-rgb), 0.3);
  cursor: default;
  pointer-events: none;
}

/* --------------------------------------------------------------------------
   Modal de countdown ("Sigues ahi?")
   -------------------------------------------------------------------------- */
.countdown-modal {
  position: fixed;
  inset: 0;
  z-index: var(--z-modal);
  display: flex;
  align-items: center;
  justify-content: center;
  padding: var(--space-4);
  background: rgba(0, 0, 0, 0.5);
  backdrop-filter: blur(6px);
  -webkit-backdrop-filter: blur(6px);
  opacity: 0;
  visibility: hidden;
  transition: opacity var(--transition-base), visibility var(--transition-base);
}

.countdown-modal.is-visible {
  opacity: 1;
  visibility: visible;
}

/* Tarjeta del modal (glassmorphism) */
.countdown-modal__content {
  background: var(--glass-bg-card);
  backdrop-filter: blur(var(--glass-blur-strong));
  -webkit-backdrop-filter: blur(var(--glass-blur-strong));
  border: 1px solid var(--glass-border-strong);
  border-radius: var(--glass-radius);
  box-shadow: var(--glass-shadow-lg);
  padding: var(--space-8);
  text-align: center;
  max-width: 380px;
  width: 100%;
  transform: scale(0.9);
  transition: transform var(--transition-base);
}

.countdown-modal.is-visible .countdown-modal__content {
  transform: scale(1);
}

.countdown-modal__title {
  font-size: var(--text-lg);
  font-weight: var(--font-semibold);
  color: var(--color-gray-900);
  margin-bottom: var(--space-2);
}

.countdown-modal__text {
  font-size: var(--text-sm);
  color: var(--color-gray-500);
  margin-bottom: var(--space-6);
}

/* Circulo de countdown SVG */
.countdown-modal__circle {
  position: relative;
  width: 100px;
  height: 100px;
  margin: 0 auto var(--space-5);
}

.countdown-modal__circle svg {
  width: 100px;
  height: 100px;
  transform: rotate(-90deg);
}

.countdown-modal__circle .countdown-track {
  fill: none;
  stroke: var(--color-gray-200);
  stroke-width: 6;
}

.countdown-modal__circle .countdown-fill {
  fill: none;
  stroke: var(--color-warning);
  stroke-width: 6;
  stroke-linecap: round;
  stroke-dasharray: 263.894; /* 2 * PI * 42 */
  stroke-dashoffset: 0;
  transition: stroke-dashoffset 1s linear;
}

/* Numero grande del countdown dentro del circulo */
.countdown-modal__time {
  position: absolute;
  inset: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: var(--text-3xl);
  font-weight: var(--font-bold);
  color: var(--color-warning);
  line-height: 1;
}

/* Boton "Seguir estudiando" */
.countdown-modal__btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-2);
  padding: var(--space-3) var(--space-8);
  min-height: 44px;
  font-family: var(--font-family);
  font-size: var(--text-base);
  font-weight: var(--font-semibold);
  line-height: 1;
  color: var(--color-white);
  background: linear-gradient(135deg, var(--color-primary) 0%, var(--color-primary-light) 100%);
  border: none;
  border-radius: var(--radius-full);
  cursor: pointer;
  box-shadow: 0 2px 8px rgba(var(--color-primary-rgb), 0.3);
  transition:
    background var(--transition-base),
    box-shadow var(--transition-base),
    transform var(--transition-base);
}

.countdown-modal__btn:hover {
  background: linear-gradient(135deg, var(--color-primary-light) 0%, var(--color-primary-lighter, #6ec6d0) 100%);
  box-shadow: 0 4px 16px rgba(var(--color-primary-rgb), 0.4);
  transform: scale(1.03);
}

.countdown-modal__btn:active {
  transform: scale(0.98);
}

/* --------------------------------------------------------------------------
   Barra de progreso reutilizable (usada en footer y en otros contextos)
   -------------------------------------------------------------------------- */
.progress-bar {
  width: 100%;
  position: relative;
}

/* Etiqueta superior (nombre + porcentaje) */
.progress-bar__label {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: var(--space-1);
  font-size: var(--text-xs);
  color: var(--color-gray-500);
}

.progress-bar__label-value {
  font-weight: var(--font-semibold);
  color: var(--color-primary);
}

/* Pista de fondo */
.progress-bar__track {
  width: 100%;
  height: 6px;
  background: var(--color-gray-200);
  border-radius: var(--radius-full);
  overflow: hidden;
}

/* Relleno con gradiente */
.progress-bar__fill {
  height: 100%;
  background: linear-gradient(90deg, var(--color-primary) 0%, var(--color-primary-light) 100%);
  border-radius: var(--radius-full);
  transition: width 0.6s cubic-bezier(0.4, 0, 0.2, 1);
  min-width: 0;
}

/* Variante animada con efecto de brillo */
.progress-bar__fill--animated {
  position: relative;
  overflow: hidden;
}

.progress-bar__fill--animated::after {
  content: '';
  position: absolute;
  top: 0;
  left: -100%;
  width: 100%;
  height: 100%;
  background: linear-gradient(
    90deg,
    transparent 0%,
    rgba(255, 255, 255, 0.3) 50%,
    transparent 100%
  );
  animation: viewerProgressShine 2s ease-in-out infinite;
}

@keyframes viewerProgressShine {
  0% { left: -100%; }
  100% { left: 100%; }
}

/* Variante animada con rayas diagonales */
.progress-bar__fill--striped {
  background-size: 30px 30px;
  background-image: linear-gradient(
    135deg,
    rgba(255, 255, 255, 0.15) 25%,
    transparent 25%,
    transparent 50%,
    rgba(255, 255, 255, 0.15) 50%,
    rgba(255, 255, 255, 0.15) 75%,
    transparent 75%,
    transparent
  );
  animation: viewerProgressStripes 1s linear infinite;
}

@keyframes viewerProgressStripes {
  from { background-position: 30px 0; }
  to { background-position: 0 0; }
}

/* --- Tamanos de la barra de progreso --- */
.progress-bar--sm .progress-bar__track {
  height: 4px;
}

.progress-bar--md .progress-bar__track {
  height: 8px;
}

.progress-bar--lg .progress-bar__track {
  height: 10px;
}

/* --------------------------------------------------------------------------
   Sidebar del indice del curso (panel lateral colapsable)
   -------------------------------------------------------------------------- */
.viewer-sidebar {
  width: 320px;
  height: 100vh;
  position: fixed;
  left: 0;
  top: 0;
  z-index: 300;
  background: var(--glass-bg-card);
  backdrop-filter: blur(var(--glass-blur));
  -webkit-backdrop-filter: blur(var(--glass-blur));
  border-right: 1px solid var(--glass-border);
  display: flex;
  flex-direction: column;
  transform: translateX(-100%);
  transition: transform 0.3s ease;
  box-shadow: 4px 0 16px rgba(0, 0, 0, 0);
}

.viewer-layout.sidebar-abierta .viewer-sidebar {
  transform: translateX(0);
  box-shadow: 4px 0 16px rgba(0, 0, 0, 0.08);
}

.viewer-sidebar__header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: var(--space-4);
  border-bottom: 1px solid var(--glass-border);
  flex-shrink: 0;
}

.viewer-sidebar__titulo {
  font-size: var(--text-sm);
  font-weight: var(--font-semibold);
  color: var(--color-gray-900);
  margin: 0;
}

.viewer-sidebar__cerrar {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 32px;
  height: 32px;
  border-radius: var(--radius-md);
  color: var(--color-gray-500);
  background: none;
  border: none;
  cursor: pointer;
  transition: background var(--transition-fast);
}

.viewer-sidebar__cerrar:hover {
  background: var(--color-gray-100);
  color: var(--color-gray-900);
}

.viewer-sidebar__cerrar svg {
  width: 20px;
  height: 20px;
}

.viewer-sidebar__body {
  flex: 1;
  overflow-y: auto;
  padding: var(--space-3);
}

.viewer-sidebar__modulo {
  margin-bottom: var(--space-3);
}

.viewer-sidebar__modulo-header {
  display: flex;
  align-items: center;
  gap: var(--space-2);
  padding: var(--space-2);
  font-size: var(--text-xs);
  font-weight: var(--font-semibold);
  color: var(--color-gray-500);
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.viewer-sidebar__modulo-num {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 20px;
  height: 20px;
  border-radius: var(--radius-sm);
  background: var(--color-primary-100, rgba(52, 144, 132, 0.1));
  color: var(--color-primary);
  font-size: var(--text-xs);
  font-weight: var(--font-bold);
  flex-shrink: 0;
}

.viewer-sidebar__leccion {
  display: flex;
  align-items: center;
  gap: var(--space-2);
  padding: var(--space-2) var(--space-3);
  border-radius: var(--radius-md);
  font-size: var(--text-sm);
  color: var(--color-gray-700);
  text-decoration: none;
  cursor: pointer;
  transition: background var(--transition-fast);
  border-left: 3px solid transparent;
}

.viewer-sidebar__leccion:hover {
  background: var(--color-gray-50);
  text-decoration: none;
}

.viewer-sidebar__leccion.es-actual {
  background: rgba(52, 144, 132, 0.08);
  border-left-color: var(--color-primary);
  font-weight: var(--font-semibold);
  color: var(--color-primary);
}

.viewer-sidebar__leccion.completada .viewer-sidebar__leccion-icono {
  color: var(--color-success);
}

.viewer-sidebar__leccion.bloqueada {
  opacity: 0.4;
  cursor: not-allowed;
}

.viewer-sidebar__leccion-icono {
  flex-shrink: 0;
  width: 16px;
  height: 16px;
}

.viewer-sidebar__leccion-icono svg {
  width: 16px;
  height: 16px;
}

.viewer-sidebar__leccion-nombre {
  flex: 1;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.viewer-sidebar__leccion-duracion {
  font-size: var(--text-xs);
  color: var(--color-gray-400);
  flex-shrink: 0;
}

/* Overlay de fondo cuando la sidebar esta abierta (solo movil) */
.viewer-sidebar__overlay {
  display: none;
}

/* --------------------------------------------------------------------------
   Responsive: Tablet (<= 1024px)
   -------------------------------------------------------------------------- */
@media (max-width: 1024px) {
  .viewer-header {
    padding: var(--space-2) var(--space-4) var(--space-3);
  }

  .viewer-content {
    padding: var(--space-4);
  }

  .viewer-content--html {
    padding: var(--space-6) var(--space-6);
  }

  .viewer-footer {
    padding: var(--space-3) var(--space-4);
  }
}

/* --------------------------------------------------------------------------
   Responsive: Movil (<= 768px)
   -------------------------------------------------------------------------- */
@media (max-width: 768px) {
  /* Ocultar barra superior con nombre curso en movil */
  .viewer-header__top {
    display: none;
  }

  .viewer-header {
    padding: var(--space-2) var(--space-3);
  }

  .viewer-header__main {
    gap: var(--space-2);
  }

  .viewer-header__breadcrumb {
    font-size: var(--text-xs);
  }

  /* Touch targets minimos 44px */
  .viewer-header__back {
    width: 44px;
    height: 44px;
  }

  .viewer-header__sidebar-toggle {
    width: 44px;
    height: 44px;
  }

  /* Sidebar: overlay fullscreen en movil */
  .viewer-sidebar {
    width: 85%;
    max-width: 360px;
    z-index: 500;
  }

  .viewer-layout.sidebar-abierta .viewer-layout__main {
    margin-left: 0;
  }

  /* Overlay de fondo */
  .viewer-sidebar__overlay {
    display: none;
    position: fixed;
    inset: 0;
    background: rgba(0, 0, 0, 0.5);
    z-index: 499;
  }

  .viewer-layout.sidebar-abierta .viewer-sidebar__overlay {
    display: block;
  }

  .viewer-sidebar__leccion {
    min-height: 44px;
    padding: var(--space-3);
  }

  .viewer-sidebar__cerrar {
    width: 44px;
    height: 44px;
  }

  /* Footer: items se reorganizan en dos filas */
  .viewer-footer {
    flex-wrap: wrap;
    gap: var(--space-2);
    padding: var(--space-2) var(--space-3);
    min-height: auto;
  }

  .viewer-footer__nav {
    order: 1;
  }

  .viewer-footer__center {
    order: 3;
    width: 100%;
    justify-content: center;
    font-size: var(--text-xs);
  }

  .viewer-completar-btn {
    order: 4;
    width: 100%;
    justify-content: center;
    min-height: 44px;
  }

  /* Botones de navegacion compactos (solo icono) */
  .viewer-footer__nav-btn span {
    display: none;
  }

  .viewer-footer__nav-btn {
    padding: var(--space-2);
    min-height: 44px;
    min-width: 44px;
    max-width: none;
    justify-content: center;
  }

  /* Contenido con menos padding */
  .viewer-content {
    padding: var(--space-3);
  }

  .viewer-content--html {
    padding: var(--space-4) var(--space-3);
  }

  .viewer-content--video {
    padding: var(--space-2);
  }

  .viewer-content--video .video-container {
    border-radius: var(--glass-radius-sm);
  }

  /* PDF ajustado al viewport movil */
  .viewer-content--pdf embed,
  .viewer-content--pdf iframe,
  .viewer-content--pdf object {
    min-height: calc(100vh - 48px - 120px);
  }

  /* Countdown modal compacto */
  .countdown-modal__content {
    padding: var(--space-6);
    max-width: 320px;
  }

  .countdown-modal__circle {
    width: 80px;
    height: 80px;
  }

  .countdown-modal__circle svg {
    width: 80px;
    height: 80px;
  }

  .countdown-modal__time {
    font-size: var(--text-2xl);
  }

  .countdown-modal__btn {
    width: 100%;
    min-height: 48px;
  }
}

/* --------------------------------------------------------------------------
   Responsive: Movil pequeno (<= 480px)
   -------------------------------------------------------------------------- */
@media (max-width: 480px) {
  .viewer-content--html p {
    font-size: var(--text-sm);
    line-height: 1.7;
  }

  .viewer-content--html h1 {
    font-size: var(--text-xl);
  }

  .viewer-content--html h2 {
    font-size: var(--text-lg);
  }

  .viewer-content--html h3 {
    font-size: var(--text-base);
  }

  .viewer-content--html img {
    margin: var(--space-2) 0;
    border-radius: var(--radius-md);
  }

  /* Tablas con scroll horizontal */
  .viewer-content--html table {
    display: block;
    overflow-x: auto;
    -webkit-overflow-scrolling: touch;
  }

  .viewer-footer__nav {
    gap: var(--space-1);
  }
}