/* ==========================================================================
   SISTEMA DE DISEÑO DE CERTIPREP STUDIO (CSS VARIABLES)
   ========================================================================== */

:root {
  /* Paleta de Colores - Modo Oscuro (Predeterminado) */
  --bg-primary: #0b0f19;
  --bg-secondary: #111827;
  --bg-tertiary: #1f2937;
  --bg-card: rgba(17, 24, 39, 0.7);
  --border-color: rgba(255, 255, 255, 0.08);
  
  --text-primary: #f3f4f6;
  --text-secondary: #9ca3af;
  --text-tertiary: #6b7280;
  
  --color-accent: #6366f1;
  --color-accent-hover: #4f46e5;
  --color-accent-light: rgba(99, 102, 241, 0.15);
  
  --color-success: #10b981;
  --color-success-light: rgba(16, 185, 129, 0.15);
  --color-error: #ef4444;
  --color-error-light: rgba(239, 68, 68, 0.15);
  
  --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
  --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
  --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.2), 0 4px 6px -2px rgba(0, 0, 0, 0.1);
  --shadow-premium: 0 20px 25px -5px rgba(0, 0, 0, 0.3), 0 10px 10px -5px rgba(0, 0, 0, 0.2);
  
  --radius-sm: 8px;
  --radius-md: 12px;
  --radius-lg: 20px;
  --radius-full: 9999px;
  
  --transition-fast: 0.15s ease;
  --transition-normal: 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  
  --font-family: 'Plus Jakarta Sans', -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
}

/* Modo Claro alternativo */
[data-theme="light"] {
  --bg-primary: #f8fafc;
  --bg-secondary: #ffffff;
  --bg-tertiary: #f1f5f9;
  --bg-card: rgba(255, 255, 255, 0.85);
  --border-color: rgba(0, 0, 0, 0.08);
  
  --text-primary: #0f172a;
  --text-secondary: #475569;
  --text-tertiary: #94a3b8;
  
  --color-accent: #4f46e5;
  --color-accent-hover: #3730a3;
  --color-accent-light: rgba(79, 70, 229, 0.1);
  
  --color-success: #059669;
  --color-success-light: rgba(5, 150, 105, 0.1);
  --color-error: #dc2626;
  --color-error-light: rgba(220, 38, 38, 0.1);
  
  --shadow-premium: 0 20px 25px -5px rgba(0, 0, 0, 0.05), 0 10px 10px -5px rgba(0, 0, 0, 0.03);
}

/* ==========================================================================
   ESTILOS GENERALES Y LAYOUT BASE
   ========================================================================== */

* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  scroll-behavior: smooth;
}

body {
  font-family: var(--font-family);
  background-color: var(--bg-primary);
  color: var(--text-primary);
  line-height: 1.6;
  transition: background-color var(--transition-normal), color var(--transition-normal);
  overflow-x: hidden;
}

/* Cabecera de la Aplicación */
.app-header {
  background-color: rgba(11, 15, 25, 0.8);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border-color);
  position: sticky;
  top: 0;
  z-index: 100;
  transition: background-color var(--transition-normal);
}

[data-theme="light"] .app-header {
  background-color: rgba(255, 255, 255, 0.8);
}

.header-container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 1rem 1.5rem;
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.app-logo {
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.logo-icon {
  font-size: 1.5rem;
  color: var(--color-accent);
  text-shadow: 0 0 10px rgba(99, 102, 241, 0.5);
  animation: pulse 2s infinite alternate;
}

.app-logo h1 {
  font-size: 1.25rem;
  font-weight: 700;
  letter-spacing: -0.025em;
}

.accent-text {
  color: var(--color-accent);
}

.header-nav {
  display: flex;
  align-items: center;
  gap: 1.5rem;
}

.nav-link {
  color: var(--text-secondary);
  text-decoration: none;
  font-weight: 500;
  font-size: 0.925rem;
  transition: color var(--transition-fast);
  position: relative;
}

.nav-link:hover, .nav-link.active {
  color: var(--text-primary);
}

.nav-link.active::after {
  content: '';
  position: absolute;
  bottom: -4px;
  left: 0;
  width: 100%;
  height: 2px;
  background-color: var(--color-accent);
  border-radius: var(--radius-full);
}

.theme-btn {
  background: var(--bg-tertiary);
  border: 1px solid var(--border-color);
  color: var(--text-primary);
  width: 36px;
  height: 36px;
  border-radius: var(--radius-sm);
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  transition: transform var(--transition-fast), background-color var(--transition-fast);
}

.theme-btn:hover {
  transform: scale(1.05);
  background-color: rgba(255, 255, 255, 0.05);
}

/* ==========================================================================
   ESTILOS DE CONTENEDORES DE ANUNCIOS (ADSENSE CLS PREVENTER)
   ========================================================================== */

.ad-container-outer {
  max-width: 1200px;
  margin: 1.5rem auto;
  padding: 0 1.5rem;
  display: flex;
  flex-direction: column;
  align-items: center;
}

.ad-label {
  font-size: 0.65rem;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--text-tertiary);
  margin-bottom: 0.25rem;
  width: 100%;
  max-width: 970px;
  text-align: center;
}

.adsense-placeholder {
  width: 100%;
  background: linear-gradient(135deg, rgba(99, 102, 241, 0.03) 0%, rgba(255, 255, 255, 0.02) 100%);
  border: 1px dashed var(--border-color);
  border-radius: var(--radius-md);
  display: flex;
  align-items: center;
  justify-content: center;
  text-align: center;
  transition: background-color var(--transition-normal);
  overflow: hidden;
}

/* 1. Leaderboard Superior */
.leaderboard-ad .adsense-placeholder {
  max-width: 970px;
  min-height: 90px; /* Altura estándar desktop */
}

/* 2. In-Article Ad (Anuncio intermedio) */
.in-article-ad .adsense-placeholder {
  max-width: 728px;
  min-height: 280px; /* Altura de bloque cuadrado/rectángulo grande */
  margin: 1.5rem 0;
}

/* 3. Sidebar Vertical Fijo */
.sidebar-ad {
  width: 100%;
  padding: 0;
  margin: 1.5rem 0 0 0;
}

.sidebar-ad .ad-label {
  max-width: 300px;
}

.sidebar-ad .adsense-placeholder {
  max-width: 300px;
  min-height: 600px; /* Tamaño clásico Half Page */
}

/* 4. Leaderboard Inferior */
.bottom-leaderboard-ad .adsense-placeholder {
  max-width: 970px;
  min-height: 90px;
}

/* Estilos para el Contenido de Reserva (Fallback e Informes) */
.ad-fallback-info {
  color: var(--text-secondary);
  font-size: 0.85rem;
  padding: 1rem;
  max-width: 500px;
  font-weight: 500;
}

.ad-fallback-info::before {
  content: '🛡️ ';
}

.ad-fallback-info-vertical {
  padding: 2rem;
  color: var(--text-secondary);
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 1rem;
  height: 100%;
}

.ad-fallback-info-vertical span {
  font-size: 0.75rem;
  font-weight: 700;
  text-transform: uppercase;
  color: var(--color-accent);
  background-color: var(--color-accent-light);
  padding: 0.25rem 0.75rem;
  border-radius: var(--radius-full);
}

.ad-fallback-info-vertical p {
  font-size: 0.85rem;
  line-height: 1.4;
  font-weight: 500;
}

/* Ajustes Responsive de Anuncios */
@media (max-width: 768px) {
  .leaderboard-ad .adsense-placeholder,
  .bottom-leaderboard-ad .adsense-placeholder {
    min-height: 50px; /* Tamaño banner móvil estándar */
  }
  
  .in-article-ad .adsense-placeholder {
    min-height: 250px;
  }
}

/* ==========================================================================
   GRID DEL LAYOUT PRINCIPAL
   ========================================================================== */

.app-main-layout {
  max-width: 1200px;
  margin: 0 auto;
  padding: 1rem 1.5rem;
}

.layout-container {
  display: grid;
  grid-template-columns: 1fr;
  gap: 2rem;
}

@media (min-width: 992px) {
  .layout-container {
    grid-template-columns: 8fr 4fr;
  }
}

/* Columnas individuales */
.main-content-column {
  display: flex;
  flex-direction: column;
  gap: 2rem;
}

.sidebar-column {
  display: flex;
  flex-direction: column;
  gap: 2rem;
}

@media (min-width: 992px) {
  .sidebar-column {
    position: sticky;
    top: calc(75px + 1rem); /* Altura de la cabecera + espacio */
    height: fit-content;
  }
}

/* ==========================================================================
   DISEÑO PREMIUM DE TARJETAS (GLASSMORPHISM)
   ========================================================================== */

.glass-card {
  background-color: var(--bg-card);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 2rem;
  box-shadow: var(--shadow-premium);
  transition: transform var(--transition-normal), border-color var(--transition-normal);
}

[data-theme="light"] .glass-card {
  box-shadow: var(--shadow-md);
}

.card-header {
  margin-bottom: 2rem;
}

.flex-header {
  display: flex;
  flex-direction: column;
  gap: 1rem;
}

@media (min-width: 640px) {
  .flex-header {
    flex-direction: row;
    justify-content: space-between;
    align-items: flex-start;
  }
}

.badge {
  display: inline-block;
  font-size: 0.725rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--color-accent);
  background-color: var(--color-accent-light);
  padding: 0.35rem 0.75rem;
  border-radius: var(--radius-full);
  margin-bottom: 0.75rem;
}

.card-header h2 {
  font-size: 1.5rem;
  font-weight: 700;
  letter-spacing: -0.02em;
  margin-bottom: 0.25rem;
}

.subtitle {
  color: var(--text-secondary);
  font-size: 0.95rem;
}

.mt-6 {
  margin-top: 1.5rem;
}

/* ==========================================================================
   COMPONENTES Y BOTONES
   ========================================================================== */

.btn {
  font-family: var(--font-family);
  font-size: 0.9rem;
  font-weight: 600;
  padding: 0.75rem 1.5rem;
  border-radius: var(--radius-md);
  border: none;
  cursor: pointer;
  transition: all var(--transition-fast);
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
}

.btn-primary {
  background-color: var(--color-accent);
  color: #ffffff;
  box-shadow: 0 4px 14px 0 rgba(99, 102, 241, 0.4);
}

.btn-primary:hover:not(:disabled) {
  background-color: var(--color-accent-hover);
  transform: translateY(-1px);
  box-shadow: 0 6px 20px 0 rgba(99, 102, 241, 0.5);
}

.btn-secondary {
  background-color: var(--bg-tertiary);
  color: var(--text-primary);
  border: 1px solid var(--border-color);
}

.btn-secondary:hover:not(:disabled) {
  background-color: rgba(255, 255, 255, 0.05);
  transform: translateY(-1px);
}

.btn-link {
  background: none;
  color: var(--text-secondary);
  padding: 0.5rem 1rem;
}

.btn-link:hover:not(:disabled) {
  color: var(--text-primary);
}

.btn:disabled {
  opacity: 0.5;
  cursor: not-allowed;
  transform: none !important;
  box-shadow: none !important;
}

/* ==========================================================================
   VISTAS DEL SIMULADOR
   ========================================================================== */

.sim-view {
  display: none;
  animation: fadeIn var(--transition-normal);
}

.sim-view.active {
  display: block;
}

/* Dashboard Multicertificación */
.cert-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 1.5rem;
  margin-top: 1rem;
}

@media (min-width: 768px) {
  .cert-grid {
    grid-template-columns: repeat(3, 1fr);
  }
}

.cert-card {
  background-color: rgba(255, 255, 255, 0.01);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: 1.5rem;
  cursor: pointer;
  display: flex;
  flex-direction: column;
  gap: 1.25rem;
  transition: transform var(--transition-normal), border-color var(--transition-normal), box-shadow var(--transition-normal), background-color var(--transition-normal);
  position: relative;
  overflow: hidden;
}

.cert-card:hover {
  transform: translateY(-4px);
  background-color: rgba(255, 255, 255, 0.02);
}

/* Colores de acento dinámicos */
.cert-card[data-cert="aws"] {
  --cert-color: #f97316;
  --cert-color-bg: rgba(249, 115, 22, 0.15);
}

.cert-card[data-cert="scrum"] {
  --cert-color: #06b6d4;
  --cert-color-bg: rgba(6, 182, 212, 0.15);
}

.cert-card[data-cert="python"] {
  --cert-color: #3b82f6;
  --cert-color-bg: rgba(59, 130, 246, 0.15);
}

.cert-card:hover {
  border-color: var(--cert-color);
  box-shadow: 0 10px 25px -5px rgba(0, 0, 0, 0.2), 0 8px 16px -8px var(--cert-color);
}

.cert-icon-wrapper {
  width: 50px;
  height: 50px;
  border-radius: var(--radius-sm);
  background-color: var(--cert-color-bg);
  color: var(--cert-color);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.5rem;
  transition: transform var(--transition-normal);
  border: 1px solid rgba(255, 255, 255, 0.05);
}

.cert-card:hover .cert-icon-wrapper {
  transform: scale(1.1) rotate(5deg);
}

.cert-info {
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
  height: 100%;
}

.cert-tag {
  display: inline-block;
  font-size: 0.65rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  padding: 0.2rem 0.5rem;
  border-radius: var(--radius-sm);
  width: fit-content;
  margin-bottom: 0.25rem;
}

.tag-aws {
  background-color: rgba(249, 115, 22, 0.1);
  color: #f97316;
  border: 1px solid rgba(249, 115, 22, 0.2);
}

.tag-scrum {
  background-color: rgba(6, 182, 212, 0.1);
  color: #06b6d4;
  border: 1px solid rgba(6, 182, 212, 0.2);
}

.tag-python {
  background-color: rgba(59, 130, 246, 0.1);
  color: #3b82f6;
  border: 1px solid rgba(59, 130, 246, 0.2);
}

.cert-info h3 {
  font-size: 1.1rem;
  font-weight: 700;
  line-height: 1.3;
}

.cert-info p {
  color: var(--text-secondary);
  font-size: 0.825rem;
  line-height: 1.4;
  flex-grow: 1;
}

.cert-meta {
  display: flex;
  gap: 1rem;
  font-size: 0.75rem;
  color: var(--text-tertiary);
  font-weight: 500;
  margin-top: 0.5rem;
  border-top: 1px solid var(--border-color);
  padding-top: 0.75rem;
}

.setup-back-action {
  margin-top: 2rem;
  display: flex;
  justify-content: center;
  border-top: 1px solid var(--border-color);
  padding-top: 1rem;
}

/* Grilla de Dificultades SPA */
.difficulty-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 1.25rem;
  margin-top: 1rem;
}

@media (min-width: 640px) {
  .difficulty-grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (min-width: 992px) {
  .difficulty-grid {
    grid-template-columns: repeat(4, 1fr);
  }
}

.diff-card {
  background-color: rgba(255, 255, 255, 0.01);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: 1.5rem 1.25rem;
  cursor: pointer;
  display: flex;
  flex-direction: column;
  align-items: center;
  text-align: center;
  gap: 0.75rem;
  transition: transform var(--transition-normal), border-color var(--transition-normal), box-shadow var(--transition-normal), background-color var(--transition-normal);
  position: relative;
  overflow: hidden;
}

.diff-card:hover {
  transform: translateY(-3px);
  background-color: rgba(255, 255, 255, 0.02);
}

/* Barras superiores de estado para coloración técnica */
.diff-status-bar {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 4px;
  background-color: var(--text-tertiary);
  transition: height var(--transition-fast);
}

.diff-card:hover .diff-status-bar {
  height: 6px;
}

.bar-green {
  --diff-color: #10b981;
  background-color: #10b981;
}

.bar-blue {
  --diff-color: #3b82f6;
  background-color: #3b82f6;
}

.bar-yellow {
  --diff-color: #f59e0b;
  background-color: #f59e0b;
}

.bar-red {
  --diff-color: #ef4444;
  background-color: #ef4444;
}

.diff-card[data-diff="principiante"] { --diff-accent: #10b981; }
.diff-card[data-diff="basico"] { --diff-accent: #3b82f6; }
.diff-card[data-diff="intermedio"] { --diff-accent: #f59e0b; }
.diff-card[data-diff="avanzado"] { --diff-accent: #ef4444; }

.diff-card:hover {
  border-color: var(--diff-accent);
  box-shadow: 0 10px 20px -5px rgba(0, 0, 0, 0.2), 0 8px 12px -8px var(--diff-accent);
}

.diff-icon {
  font-size: 2rem;
  background-color: rgba(255, 255, 255, 0.02);
  width: 54px;
  height: 54px;
  border-radius: var(--radius-full);
  display: flex;
  align-items: center;
  justify-content: center;
  border: 1px solid var(--border-color);
  margin-bottom: 0.25rem;
  transition: transform var(--transition-normal);
}

.diff-card:hover .diff-icon {
  transform: scale(1.1) rotate(-5deg);
}

.diff-card h3 {
  font-size: 1.05rem;
  font-weight: 700;
}

.diff-card p {
  color: var(--text-secondary);
  font-size: 0.775rem;
  line-height: 1.4;
  flex-grow: 1;
}

/* Spinner e Interfaz de Carga Asíncrona (Fetch) */
.loader-container {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  padding: 3rem 0;
  gap: 1.25rem;
  text-align: center;
}

.loader-spinner {
  width: 48px;
  height: 48px;
  border: 3px solid rgba(99, 102, 241, 0.1);
  border-top: 3px solid var(--color-accent);
  border-radius: var(--radius-full);
  animation: spin 1s cubic-bezier(0.4, 0, 0.2, 1) infinite;
  box-shadow: 0 0 15px rgba(99, 102, 241, 0.2);
}

.loader-text {
  font-size: 0.9rem;
  color: var(--text-secondary);
  font-weight: 500;
  letter-spacing: -0.01em;
}

@keyframes spin {
  0% {
    transform: rotate(0deg);
  }
  100% {
    transform: rotate(360deg);
  }
}

/* Configuración Inicial */
.setup-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 1.5rem;
}

@media (min-width: 640px) {
  .setup-grid {
    grid-template-columns: 1fr 1fr;
  }
}

.setup-option {
  background-color: rgba(255, 255, 255, 0.02);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: 2rem;
  text-align: center;
  transition: transform var(--transition-normal), border-color var(--transition-normal);
}

.setup-option:hover {
  transform: translateY(-3px);
  border-color: rgba(99, 102, 241, 0.3);
  background-color: rgba(255, 255, 255, 0.03);
}

.option-icon {
  font-size: 2.5rem;
  margin-bottom: 1rem;
}

.setup-option h3 {
  font-size: 1.2rem;
  margin-bottom: 0.75rem;
  font-weight: 600;
}

.setup-option p {
  color: var(--text-secondary);
  font-size: 0.875rem;
  margin-bottom: 1.5rem;
  min-height: 80px;
}

.setup-option .btn {
  width: 100%;
}

/* Barra de Estado del Test Activo */
.sim-status-bar {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 2rem;
  gap: 1rem;
}

.progress-container {
  flex-grow: 1;
}

#question-counter {
  font-size: 0.8rem;
  font-weight: 600;
  color: var(--text-secondary);
  display: block;
  margin-bottom: 0.35rem;
}

.progress-bar-bg {
  background-color: var(--bg-tertiary);
  height: 6px;
  border-radius: var(--radius-full);
  overflow: hidden;
}

.progress-bar-fill {
  background-color: var(--color-accent);
  height: 100%;
  border-radius: var(--radius-full);
  width: 0;
  transition: width var(--transition-normal);
  box-shadow: 0 0 10px rgba(99, 102, 241, 0.7);
}

.timer-display {
  display: flex;
  align-items: center;
  gap: 0.35rem;
  font-size: 0.95rem;
  font-weight: 700;
  background-color: var(--color-error-light);
  color: var(--color-error);
  padding: 0.35rem 0.75rem;
  border-radius: var(--radius-md);
  border: 1px solid rgba(239, 68, 68, 0.2);
}

.timer-display.hidden {
  display: none !important;
}

/* Pregunta y Opciones */
.question-container {
  margin-bottom: 2rem;
}

.question-container h3 {
  font-size: 1.15rem;
  font-weight: 600;
  line-height: 1.5;
  margin-bottom: 1.5rem;
}

.options-list {
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
}

.option-item {
  background-color: rgba(255, 255, 255, 0.01);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: 1rem 1.25rem;
  display: flex;
  align-items: flex-start;
  gap: 0.75rem;
  cursor: pointer;
  transition: all var(--transition-fast);
}

.option-item:hover {
  background-color: rgba(255, 255, 255, 0.03);
  border-color: rgba(255, 255, 255, 0.15);
}

.option-item.selected {
  border-color: var(--color-accent);
  background-color: var(--color-accent-light);
}

.option-radio {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 20px;
  height: 20px;
  border-radius: var(--radius-full);
  border: 2px solid var(--text-tertiary);
  margin-top: 0.15rem;
  flex-shrink: 0;
  transition: all var(--transition-fast);
}

.option-item.selected .option-radio {
  border-color: var(--color-accent);
  background-color: var(--color-accent);
}

.option-item.selected .option-radio::after {
  content: '';
  width: 8px;
  height: 8px;
  background-color: #ffffff;
  border-radius: var(--radius-full);
}

.option-text {
  font-size: 0.925rem;
  font-weight: 500;
}

/* Respuestas Evaluadas en Modo Práctica */
.option-item.correct {
  border-color: var(--color-success) !important;
  background-color: var(--color-success-light) !important;
}

.option-item.correct .option-radio {
  border-color: var(--color-success) !important;
  background-color: var(--color-success) !important;
}

.option-item.incorrect {
  border-color: var(--color-error) !important;
  background-color: var(--color-error-light) !important;
}

.option-item.incorrect .option-radio {
  border-color: var(--color-error) !important;
  background-color: var(--color-error) !important;
}

/* Caja de Explicación Detallada */
.explanation-box {
  background-color: rgba(255, 255, 255, 0.02);
  border-left: 4px solid var(--color-accent);
  border-radius: 0 var(--radius-md) var(--radius-md) 0;
  padding: 1.25rem 1.5rem;
  margin-bottom: 2rem;
  animation: slideDown var(--transition-normal);
}

.explanation-box.hidden {
  display: none !important;
}

.explanation-title {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  margin-bottom: 0.5rem;
}

.status-badge {
  font-size: 0.7rem;
  font-weight: 700;
  text-transform: uppercase;
  padding: 0.2rem 0.5rem;
  border-radius: var(--radius-sm);
}

.status-badge.correct {
  background-color: var(--color-success-light);
  color: var(--color-success);
  border: 1px solid rgba(16, 185, 129, 0.2);
}

.status-badge.incorrect {
  background-color: var(--color-error-light);
  color: var(--color-error);
  border: 1px solid rgba(239, 68, 68, 0.2);
}

.explanation-title h4 {
  font-size: 0.95rem;
  font-weight: 700;
}

#explanation-text {
  font-size: 0.9rem;
  color: var(--text-secondary);
  margin-bottom: 0.75rem;
}

.reference-link {
  font-size: 0.8rem;
  color: var(--text-tertiary);
}

.reference-link a {
  color: var(--color-accent);
  text-decoration: none;
}

.reference-link a:hover {
  text-decoration: underline;
}

.sim-actions {
  display: flex;
  justify-content: space-between;
  align-items: center;
  border-top: 1px solid var(--border-color);
  padding-top: 1.5rem;
}

/* Vista de Resultados */
.results-summary {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 2rem;
  text-align: center;
  padding: 1rem 0;
}

@media (min-width: 640px) {
  .results-summary {
    flex-direction: row;
    text-align: left;
    align-items: center;
    justify-content: center;
  }
}

.results-score-wheel {
  width: 130px;
  height: 130px;
  border-radius: var(--radius-full);
  border: 8px solid var(--color-accent);
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  box-shadow: 0 0 20px rgba(99, 102, 241, 0.2);
  flex-shrink: 0;
}

#score-percentage {
  font-size: 2rem;
  font-weight: 700;
  line-height: 1;
}

.score-label {
  font-size: 0.75rem;
  text-transform: uppercase;
  color: var(--text-secondary);
  font-weight: 600;
}

.results-stats h3 {
  font-size: 1.5rem;
  margin-bottom: 0.5rem;
}

.results-stats p {
  color: var(--text-secondary);
  font-size: 0.95rem;
  margin-bottom: 1.5rem;
}

.stats-grid {
  display: flex;
  gap: 1.5rem;
  margin-bottom: 1.5rem;
}

.stat-box {
  background-color: rgba(255, 255, 255, 0.02);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-sm);
  padding: 0.75rem 1.25rem;
  min-width: 100px;
}

.stat-val {
  display: block;
  font-size: 1.25rem;
  font-weight: 700;
  line-height: 1.2;
}

.stat-lbl {
  font-size: 0.75rem;
  color: var(--text-secondary);
}

/* ==========================================================================
   TEMPORIZADOR POMODORO
   ========================================================================== */

.pomodoro-modes {
  display: flex;
  background-color: var(--bg-tertiary);
  border: 1px solid var(--border-color);
  padding: 0.25rem;
  border-radius: var(--radius-md);
  align-self: center;
}

.pom-mode-btn {
  background: none;
  border: none;
  font-family: var(--font-family);
  font-size: 0.775rem;
  font-weight: 600;
  color: var(--text-secondary);
  padding: 0.45rem 0.85rem;
  border-radius: var(--radius-sm);
  cursor: pointer;
  transition: all var(--transition-fast);
}

.pom-mode-btn.active {
  background-color: var(--color-accent);
  color: #ffffff;
}

.pomodoro-timer-container {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 2rem;
  padding: 1.5rem 0;
}

.timer-circle-wrap {
  position: relative;
  width: 180px;
  height: 180px;
}

.timer-svg {
  width: 100%;
  height: 100%;
  transform: rotate(-90deg);
}

.timer-circle-bg {
  fill: none;
  stroke: var(--bg-tertiary);
  stroke-width: 5;
}

.timer-circle-fg {
  fill: none;
  stroke: var(--color-accent);
  stroke-width: 5;
  stroke-linecap: round;
  stroke-dasharray: 283; /* 2 * PI * r (r=45) = 282.7 */
  stroke-dashoffset: 0;
  transition: stroke-dashoffset 1s linear;
}

.timer-digits {
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  font-size: 2.25rem;
  font-weight: 700;
  letter-spacing: -0.02em;
}

.pomodoro-controls {
  display: flex;
  align-items: center;
  gap: 1rem;
}

/* ==========================================================================
   BARRA LATERAL - ESTADÍSTICAS Y HISTORIAL
   ========================================================================== */

.sidebar-card {
  padding: 1.5rem;
}

.sidebar-card h3 {
  font-size: 1.15rem;
  margin-bottom: 1.25rem;
  border-bottom: 1px solid var(--border-color);
  padding-bottom: 0.75rem;
}

.progress-summary {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1rem;
  margin-bottom: 1.5rem;
}

.prog-metric {
  background-color: rgba(255, 255, 255, 0.02);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: 1rem 0.75rem;
  text-align: center;
}

.prog-num {
  display: block;
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--color-accent);
}

.prog-lbl {
  font-size: 0.725rem;
  color: var(--text-secondary);
}

.history-list-wrapper h4 {
  font-size: 0.85rem;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--text-tertiary);
  margin-bottom: 0.75rem;
}

.history-list {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
  margin-bottom: 1rem;
}

.history-item {
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-size: 0.825rem;
  padding: 0.5rem 0.75rem;
  background-color: rgba(255, 255, 255, 0.01);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-sm);
}

.history-score {
  font-weight: 700;
}

.history-score.pass {
  color: var(--color-success);
}

.history-score.fail {
  color: var(--color-error);
}

.history-date {
  color: var(--text-tertiary);
}

.empty-history {
  font-size: 0.8rem;
  color: var(--text-tertiary);
  line-height: 1.5;
  text-align: center;
  padding: 1rem;
}

.btn-xs {
  font-size: 0.75rem;
  padding: 0.25rem 0.5rem;
  width: 100%;
}

.hidden {
  display: none !important;
}

/* ==========================================================================
   SECCIÓN EXPLICATIVA E-E-A-T
   ========================================================================== */

.about-eeat-section {
  background-color: var(--bg-secondary);
  border-top: 1px solid var(--border-color);
  border-bottom: 1px solid var(--border-color);
  padding: 4rem 1.5rem;
  margin-top: 3rem;
  transition: background-color var(--transition-normal);
}

.section-container {
  max-width: 1200px;
  margin: 0 auto;
}

.about-eeat-section h2 {
  font-size: 1.75rem;
  font-weight: 700;
  text-align: center;
  margin-bottom: 1rem;
  letter-spacing: -0.02em;
}

.section-lead {
  text-align: center;
  color: var(--text-secondary);
  max-width: 700px;
  margin: 0 auto 3rem auto;
  font-size: 1.05rem;
}

.about-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 2rem;
  margin-bottom: 3.5rem;
}

@media (min-width: 768px) {
  .about-grid {
    grid-template-columns: repeat(3, 1fr);
  }
}

.about-item h4 {
  font-size: 1.05rem;
  font-weight: 600;
  margin-bottom: 0.75rem;
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.about-item h4::before {
  content: '✦';
  color: var(--color-accent);
}

.about-item p {
  font-size: 0.875rem;
  color: var(--text-secondary);
}

/* Acordeón de FAQs */
.faq-container {
  max-width: 800px;
  margin: 0 auto 3.5rem auto;
}

.faq-container h3 {
  font-size: 1.3rem;
  margin-bottom: 1.5rem;
  text-align: center;
}

.faq-item {
  background-color: var(--bg-primary);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  margin-bottom: 0.75rem;
  overflow: hidden;
  transition: background-color var(--transition-normal);
}

.faq-item[open] {
  background-color: var(--bg-tertiary);
}

.faq-item summary {
  padding: 1rem 1.5rem;
  font-weight: 600;
  font-size: 0.95rem;
  cursor: pointer;
  outline: none;
  list-style: none;
  position: relative;
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.faq-item summary::-webkit-details-marker {
  display: none;
}

.faq-item summary::after {
  content: '+';
  font-size: 1.25rem;
  color: var(--text-secondary);
  transition: transform var(--transition-fast);
}

.faq-item[open] summary::after {
  content: '−';
}

.faq-answer {
  padding: 0 1.5rem 1.25rem 1.5rem;
  font-size: 0.9rem;
  color: var(--text-secondary);
  border-top: 1px solid var(--border-color);
  padding-top: 1rem;
}

/* Autoría y Confianza */
.author-profile-block {
  max-width: 800px;
  margin: 0 auto;
  background-color: var(--bg-primary);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 2rem;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 1.5rem;
  text-align: center;
  box-shadow: var(--shadow-sm);
  transition: background-color var(--transition-normal);
}

@media (min-width: 640px) {
  .author-profile-block {
    flex-direction: row;
    text-align: left;
    align-items: flex-start;
  }
}

.author-avatar {
  font-size: 3rem;
  background-color: var(--bg-tertiary);
  width: 80px;
  height: 80px;
  border-radius: var(--radius-full);
  display: flex;
  align-items: center;
  justify-content: center;
  border: 2px solid var(--border-color);
  flex-shrink: 0;
}

.author-details h4 {
  font-size: 1.15rem;
  margin-bottom: 0.25rem;
}

.author-title {
  font-size: 0.775rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--color-accent);
  margin-bottom: 0.75rem;
}

.author-bio {
  font-size: 0.875rem;
  color: var(--text-secondary);
  line-height: 1.5;
}

/* ==========================================================================
   PIE DE PÁGINA
   ========================================================================== */

.app-footer {
  background-color: var(--bg-primary);
  border-top: 1px solid var(--border-color);
  padding: 2rem 1.5rem;
  transition: background-color var(--transition-normal);
}

.footer-container {
  max-width: 1200px;
  margin: 0 auto;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 1rem;
  text-align: center;
}

@media (min-width: 768px) {
  .footer-container {
    flex-direction: row;
    justify-content: space-between;
    text-align: left;
  }
}

.footer-brand p {
  font-size: 0.75rem;
  color: var(--text-tertiary);
  max-width: 500px;
}

.footer-links {
  display: flex;
  gap: 1.5rem;
}

.footer-links a {
  font-size: 0.775rem;
  color: var(--text-secondary);
  text-decoration: none;
  font-weight: 500;
}

.footer-links a:hover {
  color: var(--text-primary);
}

/* ==========================================================================
   ANIMACIONES
   ========================================================================== */

@keyframes fadeIn {
  from {
    opacity: 0;
    transform: translateY(5px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

@keyframes slideDown {
  from {
    opacity: 0;
    transform: translateY(-8px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

@keyframes pulse {
  from {
    transform: scale(1);
    opacity: 0.8;
  }
  to {
    transform: scale(1.1);
    opacity: 1;
  }
}