/* ============================================
   Examina - Sistema de Exámenes Digitales
   Design System basado en horarios
   ============================================ */

:root {
    /* Light Theme */
    --bg-primary: #f8fafc;
    --bg-secondary: #ffffff;
    --bg-tertiary: #f1f5f9;
    --text-primary: #0f172a;
    --text-secondary: #475569;
    --text-muted: #94a3b8;
    --border-color: #e2e8f0;
    --accent-primary: #3b82f6;
    --accent-secondary: #8b5cf6;
    --accent-success: #10b981;
    --accent-warning: #f59e0b;
    --accent-danger: #ef4444;
    --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, 0.1), 0 4px 6px -2px rgba(0, 0, 0, 0.05);
    --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.1), 0 10px 10px -5px rgba(0, 0, 0, 0.04);
    --radius-sm: 6px;
    --radius-md: 8px;
    --radius-lg: 12px;
    --radius-xl: 16px;
    --transition: all 0.2s cubic-bezier(0.4, 0, 0.2, 1);
    --sidebar-width: 280px;
    --sidebar-collapsed: 80px;
}

[data-theme="dark"] {
    --bg-primary: #0f172a;
    --bg-secondary: #1e293b;
    --bg-tertiary: #334155;
    --text-primary: #f1f5f9;
    --text-secondary: #cbd5e1;
    --text-muted: #64748b;
    --border-color: #334155;
    --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.3);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.4), 0 2px 4px -1px rgba(0, 0, 0, 0.3);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.4), 0 4px 6px -2px rgba(0, 0, 0, 0.3);
    --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.5), 0 10px 10px -5px rgba(0, 0, 0, 0.3);
}

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

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    background: var(--bg-primary);
    color: var(--text-primary);
    display: flex;
    min-height: 100vh;
    line-height: 1.6;
    transition: var(--transition);
}

/* ============================================
   Sidebar Navigation
   ============================================ */

#sidebar {
    flex: 0 0 var(--sidebar-width);
    width: var(--sidebar-width);
}

.navbar {
    width: 100%;
    background: var(--bg-secondary);
    border-right: 1px solid var(--border-color);
    padding: 1.5rem 1rem;
    display: flex;
    flex-direction: column;
    position: sticky;
    top: 0;
    height: 100vh;
    overflow-y: auto;
    transition: var(--transition);
    z-index: 100;
    box-shadow: var(--shadow-sm);
}

.nav-brand {
    font-size: 0.95rem;
    font-weight: 700;
    color: var(--accent-primary);
    margin-bottom: 2rem;
    display: flex;
    align-items: flex-start;
    gap: 0.75rem;
    padding: 0 0.5rem;
    line-height: 1.3;
}

.nav-brand::before {
    content: '📝';
    font-size: 1.5rem;
    flex-shrink: 0;
    margin-top: 0.1rem;
}

.nav-logout {
    margin-top: auto;
    padding-top: 1rem;
    border-top: 1px solid var(--border-color);
}

.btn-logout {
    width: 100%;
}

/* La barra con hamburguesa y el fondo del cajón solo existen en móvil */
.mobile-bar,
.nav-backdrop {
    display: none;
}

.navbar.collapsed .nav-brand span {
    display: none;
}

.nav-menu {
    list-style: none;
    margin-bottom: 1.5rem;
}

.nav-menu li {
    margin-bottom: 0.25rem;
}

.nav-menu a {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    padding: 0.75rem 1rem;
    color: var(--text-secondary);
    text-decoration: none;
    border-radius: var(--radius-md);
    transition: var(--transition);
    font-weight: 500;
    font-size: 0.95rem;
}

.nav-menu a:hover {
    background: var(--bg-tertiary);
    color: var(--accent-primary);
    transform: translateX(4px);
}

.nav-menu a.active {
    background: linear-gradient(135deg, var(--accent-primary), var(--accent-secondary));
    color: white;
    box-shadow: var(--shadow-md);
}

.nav-menu a::before {
    font-size: 1.25rem;
}

.nav-menu a[data-page="inicio"]::before { content: '🏠'; }
.nav-menu a[data-page="instituciones"]::before { content: '🏛️'; }
.nav-menu a[data-page="profesores"]::before { content: '👨‍🏫'; }
.nav-menu a[data-page="alumnos"]::before { content: '👥'; }
.nav-menu a[data-page="materias"]::before { content: '📚'; }
.nav-menu a[data-page="grupos"]::before { content: '🏫'; }
.nav-menu a[data-page="smtp"]::before { content: '📧'; }
.nav-menu a[data-page="actividad"]::before { content: '📋'; }
.nav-menu a[data-page="ejercicios"]::before { content: '📝'; }
.nav-menu a[data-page="calificar"]::before { content: '✅'; }
.nav-menu a[data-page="resultados"]::before { content: '📈'; }
.nav-menu a[data-page="pendientes"]::before { content: '📅'; }
.nav-menu a[data-page="calificaciones"]::before { content: '💯'; }

.navbar.collapsed .nav-menu a span {
    display: none;
}

.nav-section {
    margin-top: 1rem;
    padding-top: 1rem;
    border-top: 1px solid var(--border-color);
}

.nav-section-title {
    font-size: 0.75rem;
    font-weight: 600;
    text-transform: uppercase;
    color: var(--text-muted);
    padding: 0 1rem;
    margin-bottom: 0.5rem;
    letter-spacing: 0.05em;
}

.navbar.collapsed .nav-section-title {
    display: none;
}

.nav-tree {
    list-style: none;
    max-height: 300px;
    overflow-y: auto;
}

.nav-tree-item {
    padding: 0.5rem 1rem 0.5rem 2rem;
    color: var(--text-secondary);
    cursor: pointer;
    border-radius: var(--radius-md);
    transition: var(--transition);
    font-size: 0.9rem;
    margin-bottom: 0.25rem;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}

.nav-tree-item:hover {
    background: var(--bg-tertiary);
    color: var(--accent-primary);
}

.nav-tree-item.active {
    background: var(--accent-primary);
    color: white;
    font-weight: 600;
}

.navbar.collapsed .nav-tree-item {
    padding: 0.5rem;
    text-align: center;
}

/* Theme Toggle */
.theme-toggle {
    margin-top: auto;
    padding: 1rem;
    border-top: 1px solid var(--border-color);
}

.theme-toggle-btn {
    width: 100%;
    padding: 0.75rem;
    background: var(--bg-tertiary);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    color: var(--text-primary);
    cursor: pointer;
    transition: var(--transition);
    font-size: 1.25rem;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
}

.theme-toggle-btn:hover {
    background: var(--accent-primary);
    color: white;
    transform: scale(1.05);
}

.navbar.collapsed .theme-toggle-btn span {
    display: none;
}

/* ============================================
   Main Content
   ============================================ */

.main-content,
#app {
    flex: 1 1 auto;
    min-width: 0;
    padding: 2rem;
    transition: var(--transition);
}

/* ============================================
   Cards
   ============================================ */

.card {
    background: var(--bg-secondary);
    border-radius: var(--radius-lg);
    padding: 1.5rem;
    margin-bottom: 1.5rem;
    box-shadow: var(--shadow-md);
    border: 1px solid var(--border-color);
    transition: var(--transition);
    animation: fadeIn 0.3s ease-in;
}

.card:hover {
    box-shadow: var(--shadow-lg);
    transform: translateY(-2px);
}

.card h2 {
    color: var(--text-primary);
    margin-bottom: 1.5rem;
    font-size: 1.5rem;
    font-weight: 700;
    display: flex;
    align-items: center;
    gap: 0.75rem;
}

.card h3 {
    color: var(--text-primary);
    margin-bottom: 1rem;
    font-size: 1.25rem;
    font-weight: 600;
}

/* ============================================
   Forms
   ============================================ */

.form-group {
    margin-bottom: 1.25rem;
}

.form-group label {
    display: block;
    margin-bottom: 0.5rem;
    color: var(--text-secondary);
    font-weight: 500;
    font-size: 0.9rem;
}

input[type="text"],
input[type="email"],
input[type="tel"],
input[type="number"],
input[type="time"],
input[type="password"],
input[type="datetime-local"],
input[type="date"],
input[type="url"],
select,
textarea {
    width: 100%;
    padding: 0.75rem 1rem;
    border: 2px solid var(--border-color);
    border-radius: var(--radius-md);
    font-size: 0.95rem;
    transition: var(--transition);
    background: var(--bg-secondary);
    color: var(--text-primary);
    font-family: inherit;
}

/* Los formularios marcan sus campos con .form-control; la regla por tipo de
   input dejaba fuera password, datetime-local y file. */
.form-control {
    width: 100%;
    padding: 0.75rem 1rem;
    border: 2px solid var(--border-color);
    border-radius: var(--radius-md);
    font-size: 0.95rem;
    transition: var(--transition);
    background: var(--bg-secondary);
    color: var(--text-primary);
    font-family: inherit;
}

input[type="file"].form-control {
    padding: 0.6rem 0.75rem;
    border-style: dashed;
    font-size: 0.9rem;
    cursor: pointer;
}

input[type="file"].form-control::file-selector-button {
    margin-right: 0.75rem;
    padding: 0.45rem 0.9rem;
    border: none;
    border-radius: var(--radius-sm);
    background: var(--accent-primary);
    color: #fff;
    font: inherit;
    font-size: 0.85rem;
    cursor: pointer;
}

input:focus,
select:focus,
textarea:focus {
    outline: none;
    border-color: var(--accent-primary);
    box-shadow: 0 0 0 3px rgba(59, 130, 246, 0.1);
}

input::placeholder {
    color: var(--text-muted);
}

/* ============================================
   Buttons
   ============================================ */

.btn {
    padding: 0.75rem 1.5rem;
    border: none;
    border-radius: var(--radius-md);
    cursor: pointer;
    font-size: 0.95rem;
    font-weight: 600;
    transition: var(--transition);
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    text-decoration: none;
    box-shadow: var(--shadow-sm);
}

.btn:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-md);
}

.btn:active {
    transform: translateY(0);
}

.btn-primary {
    background: linear-gradient(135deg, var(--accent-primary), var(--accent-secondary));
    color: white;
}

.btn-primary:hover {
    background: linear-gradient(135deg, #2563eb, #7c3aed);
}

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

.btn-secondary:hover {
    background: var(--border-color);
}

.btn-success {
    background: linear-gradient(135deg, var(--accent-success), #059669);
    color: white;
}

.btn-success:hover {
    background: linear-gradient(135deg, #059669, #047857);
}

.btn-danger {
    background: linear-gradient(135deg, var(--accent-danger), #dc2626);
    color: white;
}

.btn-danger:hover {
    background: linear-gradient(135deg, #dc2626, #b91c1c);
}

.btn-warning {
    background: linear-gradient(135deg, var(--accent-warning), #d97706);
    color: white;
}

.btn-sm {
    padding: 0.5rem 1rem;
    font-size: 0.875rem;
}

.actions {
    display: flex;
    gap: 0.5rem;
    flex-wrap: wrap;
}

/* ============================================
   Filtros de lista
   ============================================ */

/* Casilla suelta en la barra de filtros: alineada con los selects y clicable en todo el texto */
.filtro-check {
    display: flex;
    align-items: center;
    gap: 0.4rem;
    flex: 1;
    min-width: 190px;
    color: var(--text-secondary);
    font-size: 0.9rem;
    cursor: pointer;
}

.filtro-check input {
    width: 1.1rem;
    height: 1.1rem;
    accent-color: var(--accent-primary);
    cursor: pointer;
}

/* ============================================
   Tables
   ============================================ */

/* Contenedor que Components pone alrededor de cada <table>: en pantallas
   estrechas la tabla desliza aquí en vez de ensanchar toda la página. */
.table-scroll {
    overflow-x: auto;
    -webkit-overflow-scrolling: touch;
    scrollbar-width: thin;
}

table {
    width: 100%;
    border-collapse: separate;
    border-spacing: 0;
    background: var(--bg-secondary);
    border-radius: var(--radius-lg);
    overflow: hidden;
    box-shadow: var(--shadow-md);
}

table thead {
    background: linear-gradient(135deg, var(--accent-primary), var(--accent-secondary));
    color: white;
}

table th {
    padding: 1rem;
    text-align: left;
    font-weight: 600;
    font-size: 0.9rem;
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

table td {
    padding: 1rem;
    border-top: 1px solid var(--border-color);
    color: var(--text-primary);
}

/* La última columna casi siempre concentra las acciones: sin esto los botones
   se apilan uno sobre otro y cada fila mide el triple de alto. */
table td:last-child {
    white-space: nowrap;
}

table tbody tr {
    transition: var(--transition);
}

table tbody tr:hover {
    background: var(--bg-tertiary);
}

table th[onclick] {
    cursor: pointer;
    user-select: none;
    transition: var(--transition);
}

table th[onclick]:hover {
    background: rgba(255, 255, 255, 0.1);
}

.sort-indicator {
    font-size: 0.7rem;
    margin-left: 0.25rem;
}

/* ============================================
   Schedule Grid (Modern Calendar View)
   ============================================ */

.schedule-container {
    background: var(--bg-secondary);
    border-radius: var(--radius-lg);
    padding: 1.5rem;
    box-shadow: var(--shadow-lg);
    overflow-x: auto;
}

.schedule-grid {
    display: grid;
    gap: 2px;
    background: var(--border-color);
    border-radius: var(--radius-md);
    overflow: hidden;
    min-width: 800px;
}

.schedule-header {
    background: linear-gradient(135deg, var(--accent-primary), var(--accent-secondary));
    color: white;
    padding: 1rem;
    font-weight: 600;
    text-align: center;
    font-size: 0.95rem;
}

.schedule-time {
    background: var(--bg-tertiary);
    padding: 0.75rem;
    font-weight: 600;
    text-align: center;
    font-size: 0.85rem;
    color: var(--text-secondary);
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    min-width: 100px;
}

.schedule-cell {
    background: var(--bg-secondary);
    padding: 0.75rem;
    min-height: 80px;
    cursor: pointer;
    transition: var(--transition);
    position: relative;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    text-align: center;
}

.schedule-cell:hover {
    background: var(--bg-tertiary);
    transform: scale(1.02);
    z-index: 10;
    box-shadow: var(--shadow-md);
}

.schedule-cell.occupied {
    color: white;
    font-weight: 500;
    border-radius: var(--radius-sm);
    margin: 2px;
}

.schedule-cell.occupied:hover {
    transform: scale(1.05);
    box-shadow: var(--shadow-lg);
}

.schedule-cell .subject-name {
    font-size: 0.9rem;
    font-weight: 700;
    margin-bottom: 0.25rem;
}

.schedule-cell .teacher-name {
    font-size: 0.75rem;
    opacity: 0.9;
}

.schedule-cell.receso {
    background: repeating-linear-gradient(
        45deg,
        var(--bg-tertiary),
        var(--bg-tertiary) 10px,
        var(--border-color) 10px,
        var(--border-color) 20px
    );
    color: var(--text-muted);
    font-style: italic;
    cursor: not-allowed;
}

.schedule-cell[draggable="true"] {
    cursor: grab;
}

.schedule-cell[draggable="true"]:active {
    cursor: grabbing;
}

.schedule-cell.drag-over {
    background: rgba(59, 130, 246, 0.2);
    border: 2px dashed var(--accent-primary);
}

/* ============================================
   Instance Panel (Draggable Items)
   ============================================ */

.instance-panel {
    background: var(--bg-secondary);
    border-radius: var(--radius-lg);
    padding: 1.5rem;
    box-shadow: var(--shadow-lg);
    max-height: calc(100vh - 200px);
    overflow-y: auto;
    position: sticky;
    top: 2rem;
}

.instance-panel h3 {
    margin-bottom: 1rem;
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.instance-filter {
    margin-bottom: 1rem;
}

.instance-filter input {
    width: 100%;
    padding: 0.75rem 1rem;
    border: 2px solid var(--border-color);
    border-radius: var(--radius-md);
    font-size: 0.9rem;
    transition: var(--transition);
}

.instance-filter input:focus {
    outline: none;
    border-color: var(--accent-primary);
    box-shadow: 0 0 0 3px rgba(59, 130, 246, 0.1);
}

.instance-item {
    padding: 0.75rem 1rem;
    margin-bottom: 0.5rem;
    border-radius: var(--radius-md);
    cursor: grab;
    transition: var(--transition);
    display: flex;
    justify-content: space-between;
    align-items: center;
    color: white;
    font-weight: 500;
    box-shadow: var(--shadow-sm);
}

.instance-item:hover {
    transform: translateX(4px);
    box-shadow: var(--shadow-md);
}

.instance-item:active {
    cursor: grabbing;
}

.instance-item.placed {
    opacity: 0.4;
    cursor: not-allowed;
    text-decoration: line-through;
}

.instance-item .instance-info {
    display: flex;
    flex-direction: column;
    gap: 0.25rem;
}

.instance-item .instance-name {
    font-size: 0.9rem;
    font-weight: 700;
}

.instance-item .instance-teacher {
    font-size: 0.75rem;
    opacity: 0.9;
}

.instance-item .instance-check {
    font-size: 1.25rem;
}

.instance-summary {
    margin-top: 1rem;
    padding-top: 1rem;
    border-top: 2px solid var(--border-color);
    font-size: 0.9rem;
    color: var(--text-secondary);
}

.instance-summary strong {
    color: var(--accent-primary);
    font-size: 1.1rem;
}

/* ============================================
   Page Header
   ============================================ */

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

.page-header-inner {
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    gap: 0.75rem 1rem;
}

.page-header h2 {
    font-size: 1.75rem;
    font-weight: 700;
    color: var(--text-primary);
    line-height: 1.2;
    margin-bottom: 0.25rem;
}

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

.page-header-actions {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
}

/* ============================================
   Stats Dashboard
   ============================================ */

.stats-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 1.5rem;
    margin-bottom: 2rem;
}

.stat-card {
    background: var(--bg-secondary);
    border-radius: var(--radius-lg);
    padding: 1.5rem;
    box-shadow: var(--shadow-md);
    border: 1px solid var(--border-color);
    transition: var(--transition);
    position: relative;
    overflow: hidden;
    min-width: 0;
}

/* Tarjeta que además es enlace: mantiene la tipografia del panel y avisa de que se puede pinchar */
.stat-card-enlace {
    display: block;
    color: inherit;
    text-decoration: none;
}

.stat-card-enlace:hover {
    transform: translateY(-2px);
    border-color: var(--stat-color, var(--accent-primary));
}

.stat-card-primary { --stat-color: var(--accent-primary); }
.stat-card-success { --stat-color: var(--accent-success); }
.stat-card-warning { --stat-color: var(--accent-warning); }
.stat-card-danger  { --stat-color: var(--accent-danger); }
.stat-card-info    { --stat-color: var(--accent-secondary); }

.stat-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 4px;
    height: 100%;
    background: var(--stat-color, var(--accent-primary));
}

.stat-card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-lg);
}

.stat-card h3 {
    font-size: 0.8rem;
    color: var(--text-muted);
    text-transform: uppercase;
    letter-spacing: 0.05em;
    margin-bottom: 0.5rem;
    padding-right: 1.5rem;
}

.stat-card .stat-value {
    font-size: 2.5rem;
    font-weight: 700;
    color: var(--stat-color, var(--accent-primary));
    line-height: 1;
}

.stat-card .stat-label {
    font-size: 0.875rem;
    color: var(--text-secondary);
    margin-top: 0.5rem;
}

.stat-card .stat-icon {
    position: absolute;
    top: 1rem;
    right: 1rem;
    font-size: 2rem;
    opacity: 0.2;
}

/* ============================================
   Lista de actividad
   ============================================ */

.actividad-lista {
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
}

.actividad-row {
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    gap: 0.5rem 1rem;
    padding: 0.75rem;
    background: var(--bg-tertiary);
    border-radius: var(--radius-md);
}

.actividad-who {
    display: flex;
    align-items: center;
    flex-wrap: wrap;
    gap: 0.5rem;
    min-width: 0;
}

.actividad-ejercicio {
    color: var(--text-secondary);
}

.actividad-fecha {
    color: var(--text-secondary);
    font-size: 0.9rem;
    white-space: nowrap;
}

/* ============================================
   Carga masiva (plantilla, vista previa y reporte)
   ============================================ */

.carga-masiva .carga-cab {
    display: flex;
    justify-content: space-between;
    align-items: flex-start;
    gap: 1rem;
    flex-wrap: wrap;
}

.carga-masiva h3 {
    margin-bottom: 0.25rem;
}

.carga-nota {
    color: var(--text-secondary);
    font-size: 0.9rem;
    margin-top: 0.25rem;
}

.carga-columnas {
    list-style: none;
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
    margin: 1rem 0;
}

.carga-columna {
    padding: 0.3rem 0.7rem;
    border: 1px solid var(--border-color);
    border-radius: 999px;
    background: var(--bg-tertiary);
    color: var(--text-secondary);
    font-size: 0.82rem;
    font-weight: 600;
}

.carga-columna.es-obligatoria {
    border-color: var(--accent-primary);
    color: var(--accent-primary);
    background: rgba(59, 130, 246, 0.08);
}

.carga-previa {
    margin: 0.5rem 0 1rem;
}

.carga-aviso {
    padding: 0.6rem 0.9rem;
    border-radius: var(--radius-md);
    font-size: 0.9rem;
}

.carga-aviso.es-ok {
    background: rgba(16, 185, 129, 0.1);
    color: var(--accent-success);
}

.carga-aviso.es-error {
    background: rgba(239, 68, 68, 0.1);
    color: var(--accent-danger);
}

.carga-tabla {
    font-size: 0.85rem;
    margin-top: 0.75rem;
}

.carga-acciones {
    display: flex;
    gap: 0.5rem;
    flex-wrap: wrap;
}

.carga-resumen {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
    margin-top: 1.25rem;
}

.carga-dato {
    padding: 0.35rem 0.8rem;
    border-radius: 999px;
    background: var(--bg-tertiary);
    font-size: 0.85rem;
    font-weight: 600;
    color: var(--text-secondary);
}

.carga-dato.es-ok {
    color: var(--accent-success);
}

.carga-dato.es-error {
    color: var(--accent-danger);
}

.carga-errores {
    margin-top: 0.75rem;
    max-height: 220px;
    overflow-y: auto;
    padding: 0.75rem 1rem;
    border-radius: var(--radius-md);
    background: rgba(239, 68, 68, 0.07);
    font-size: 0.88rem;
}

.carga-errores p {
    color: var(--accent-danger);
}

.carga-detalle {
    margin-top: 1rem;
}

.carga-detalle summary {
    cursor: pointer;
    font-weight: 600;
}

/* ============================================
   Toast Notifications (SweetAlert2 Custom)
   ============================================ */

.swal2-popup {
    border-radius: var(--radius-lg) !important;
    box-shadow: var(--shadow-xl) !important;
}

.swal2-toast {
    box-shadow: var(--shadow-lg) !important;
    border-radius: var(--radius-md) !important;
}

/* ============================================
   Animations
   ============================================ */

@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translateY(10px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

@keyframes slideIn {
    from {
        transform: translateX(-100%);
    }
    to {
        transform: translateX(0);
    }
}

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

.fade-in {
    animation: fadeIn 0.3s ease-in;
}

.slide-in {
    animation: slideIn 0.3s ease-out;
}

/* ============================================
   Utilities
   ============================================ */

.text-center { text-align: center; }
.text-right { text-align: right; }
.text-muted { color: var(--text-muted); }
.text-success { color: var(--accent-success); }
.text-warning { color: var(--accent-warning); }
.text-danger { color: var(--accent-danger); }

.mt-1 { margin-top: 0.5rem; }
.mt-2 { margin-top: 1rem; }
.mt-3 { margin-top: 1.5rem; }
.mb-1 { margin-bottom: 0.5rem; }
.mb-2 { margin-bottom: 1rem; }
.mb-3 { margin-bottom: 1.5rem; }

.flex { display: flex; }
.flex-col { flex-direction: column; }
.items-center { align-items: center; }
.justify-between { justify-content: space-between; }
.gap-1 { gap: 0.5rem; }
.gap-2 { gap: 1rem; }
.gap-3 { gap: 1.5rem; }

/* ============================================
   Responsive (layout base — el menú móvil se define abajo, en Mobile First)
   ============================================ */

@media (max-width: 1100px) {
    :root {
        --sidebar-width: 220px;
    }

    .stats-grid {
        grid-template-columns: repeat(2, 1fr);
    }
}

/* ============================================
   Print Styles
   ============================================ */

@media print {
    .navbar,
    .theme-toggle,
    .btn,
    .actions,
    .instance-panel,
    #btnAutocompletar,
    #btnGenerar,
    #btnReset,
    #btnExportar {
        display: none !important;
    }
    
    .container {
        margin: 0;
        padding: 0;
        width: 100%;
    }
    
    .card {
        box-shadow: none;
        border: none;
        page-break-inside: avoid;
    }
    
    .schedule-cell.occupied {
        -webkit-print-color-adjust: exact !important;
        print-color-adjust: exact !important;
        color-adjust: exact !important;
    }
}

/* ============================================
   Scrollbar Styling
   ============================================ */

::-webkit-scrollbar {
    width: 8px;
    height: 8px;
}

::-webkit-scrollbar-track {
    background: var(--bg-tertiary);
    border-radius: var(--radius-sm);
}

::-webkit-scrollbar-thumb {
    background: var(--border-color);
    border-radius: var(--radius-sm);
}

::-webkit-scrollbar-thumb:hover {
    background: var(--text-muted);
}

/* ============================================
   Loading States
   ============================================ */

.skeleton {
    background: linear-gradient(90deg, var(--bg-tertiary) 25%, var(--border-color) 50%, var(--bg-tertiary) 75%);
    background-size: 200% 100%;
    animation: loading 1.5s infinite;
    border-radius: var(--radius-sm);
}

@keyframes loading {
    0% {
        background-position: 200% 0;
    }
    100% {
        background-position: -200% 0;
    }
}

/* ============================================
   Badges (definición única: ver "Status Badges" al final)
   ============================================ */

/* ============================================
   Modal Enhancements
   ============================================ */

.modal-backdrop {
    backdrop-filter: blur(4px);
}

.modal-content {
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-xl);
    animation: fadeIn 0.2s ease-out;
}

/* ============================================
   Examina - Login Page
   ============================================ */

.login-container {
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    background: linear-gradient(135deg, var(--accent-primary), var(--accent-secondary));
    padding: 1rem;
}

.login-card {
    background: var(--bg-secondary);
    border-radius: var(--radius-xl);
    box-shadow: var(--shadow-xl);
    padding: 3rem;
    width: 100%;
    max-width: 450px;
}

.login-header {
    text-align: center;
    margin-bottom: 2rem;
}

.login-header h1 {
    font-size: 2rem;
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: 0.5rem;
}

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

.login-form .form-group {
    margin-bottom: 1.5rem;
}

.login-form label {
    display: block;
    font-weight: 500;
    color: var(--text-primary);
    margin-bottom: 0.5rem;
    font-size: 0.9rem;
}

.login-form input {
    width: 100%;
    padding: 0.75rem 1rem;
    border: 2px solid var(--border-color);
    border-radius: var(--radius-md);
    font-size: 1rem;
    transition: var(--transition);
    background: var(--bg-primary);
    color: var(--text-primary);
}

.login-form input:focus {
    outline: none;
    border-color: var(--accent-primary);
    box-shadow: 0 0 0 3px rgba(59, 130, 246, 0.1);
}

.login-form button {
    width: 100%;
    padding: 0.875rem;
    background: linear-gradient(135deg, var(--accent-primary), var(--accent-secondary));
    color: white;
    border: none;
    border-radius: var(--radius-md);
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    transition: var(--transition);
}

.login-form button:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-lg);
}

.login-form button:disabled {
    opacity: 0.6;
    cursor: not-allowed;
    transform: none;
}

.login-error {
    background: rgba(239, 68, 68, 0.1);
    color: var(--accent-danger);
    padding: 0.75rem 1rem;
    border-radius: var(--radius-md);
    margin-bottom: 1rem;
    font-size: 0.9rem;
    display: none;
}

.login-error.show {
    display: block;
}

/* ============================================
   Examina - Multimedia Upload
   ============================================ */

.upload-area {
    border: 2px dashed var(--border-color);
    border-radius: var(--radius-lg);
    padding: 2rem;
    text-align: center;
    cursor: pointer;
    transition: var(--transition);
    background: var(--bg-tertiary);
}

.upload-area:hover {
    border-color: var(--accent-primary);
    background: var(--bg-secondary);
}

.upload-area.dragover {
    border-color: var(--accent-primary);
    background: rgba(59, 130, 246, 0.05);
}

.upload-icon {
    font-size: 3rem;
    margin-bottom: 1rem;
}

.upload-text {
    color: var(--text-secondary);
    margin-bottom: 1rem;
}

.upload-buttons {
    display: flex;
    gap: 0.5rem;
    flex-wrap: wrap;
    justify-content: center;
}

.upload-btn {
    padding: 0.5rem 1rem;
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    background: var(--bg-secondary);
    color: var(--text-primary);
    cursor: pointer;
    transition: var(--transition);
    font-size: 0.9rem;
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.upload-btn:hover {
    background: var(--bg-tertiary);
    border-color: var(--accent-primary);
}

.upload-preview {
    margin-top: 1rem;
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(150px, 1fr));
    gap: 1rem;
}

.preview-item {
    position: relative;
    border-radius: var(--radius-md);
    overflow: hidden;
    background: var(--bg-tertiary);
    aspect-ratio: 1;
}

.preview-item img,
.preview-item video {
    width: 100%;
    height: 100%;
    object-fit: cover;
}

.preview-item audio {
    width: 100%;
    padding: 1rem;
}

.preview-item .remove-btn {
    position: absolute;
    top: 0.5rem;
    right: 0.5rem;
    background: var(--accent-danger);
    color: white;
    border: none;
    border-radius: 50%;
    width: 28px;
    height: 28px;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.2rem;
}

/* ============================================
   Examina - Mobile First (Alumno)
   ============================================ */

@media (max-width: 768px) {
    body {
        flex-direction: column;
    }

    #sidebar {
        flex: 0 0 auto;
        width: 100%;
        /* El contenedor es el que se fija: si lo hacemos sticky en .navbar,
           la barra mide lo mismo que su hijo y se va al hacer scroll. */
        position: sticky;
        top: 0;
        z-index: 300;
    }

    /* Barra superior: hamburguesa + marca. El menú ya no come espacio en dos filas. */
    .mobile-bar {
        display: flex;
        align-items: center;
        gap: 0.6rem;
        padding: 0.5rem 0.75rem;
        background: var(--bg-secondary);
        border-bottom: 1px solid var(--border-color);
        box-shadow: var(--shadow-sm);
    }

    .nav-toggle {
        display: inline-flex;
        align-items: center;
        justify-content: center;
        width: 40px;
        height: 40px;
        font-size: 1.3rem;
        line-height: 1;
        color: var(--text-primary);
        background: var(--bg-tertiary);
        border: 1px solid var(--border-color);
        border-radius: var(--radius-md);
        cursor: pointer;
    }

    .nav-toggle:active {
        background: var(--accent-primary);
        color: #fff;
        border-color: var(--accent-primary);
    }

    .mobile-brand {
        font-weight: 700;
        color: var(--accent-primary);
    }

    /* El menú se vuelve cajón que entra desde la izquierda */
    .navbar {
        position: fixed;
        top: 0;
        left: 0;
        z-index: 400;
        width: min(82vw, 300px);
        height: 100vh;
        height: 100dvh;
        flex-direction: column;
        align-items: stretch;
        gap: 0;
        padding: 1.25rem 0.75rem 1rem;
        overflow-y: auto;
        border-right: 1px solid var(--border-color);
        transform: translateX(-100%);
        transition: transform 0.25s ease;
    }

    .navbar.nav-open {
        transform: none;
        box-shadow: var(--shadow-lg);
    }

    .nav-backdrop {
        display: block;
        position: fixed;
        inset: 0;
        z-index: 390;
        background: rgba(15, 23, 42, 0.5);
        opacity: 0;
        pointer-events: none;
        transition: opacity 0.2s ease;
    }

    .nav-backdrop.show {
        opacity: 1;
        pointer-events: auto;
    }

    body.nav-bloqueado {
        overflow: hidden;
    }

    .nav-brand {
        margin-bottom: 1.5rem;
        font-size: 0.95rem;
    }

    .nav-scroll {
        display: block;
        overflow: visible;
        margin: 0;
        padding: 0;
    }

    .nav-menu {
        display: block;
        margin-bottom: 1.25rem;
    }

    .nav-menu li {
        margin-bottom: 0.25rem;
    }

    .nav-menu a {
        padding: 0.7rem 0.85rem;
        white-space: normal;
        font-size: 0.95rem;
    }

    .nav-menu a:hover {
        transform: none;
    }

    .nav-section {
        display: block;
        margin-top: 0.5rem;
        padding-top: 0.75rem;
        border-top: 1px solid var(--border-color);
    }

    .nav-section-title {
        display: block;
    }

    .nav-logout {
        margin-top: auto;
        padding-top: 0.75rem;
        border-top: 1px solid var(--border-color);
    }

    .btn-logout {
        width: 100%;
        white-space: nowrap;
    }

    .main-content,
    #app {
        padding: 1rem;
        flex: 1 1 auto;
    }

    .card {
        padding: 1rem;
    }

    .form-grid {
        grid-template-columns: 1fr;
    }

    /* Tarjetas de resumen en dos columnas: cinco tarjetas gigantes apiladas hacen
       que el dashboard no quepa en la pantalla. */
    .stats-grid {
        grid-template-columns: repeat(2, 1fr);
        gap: 0.75rem;
        margin-bottom: 1.25rem;
    }

    .stat-card {
        padding: 0.85rem 0.75rem;
    }

    .stat-card h3 {
        font-size: 0.65rem;
        margin-bottom: 0.25rem;
        padding-right: 1rem;
    }

    .stat-card .stat-value {
        font-size: 1.6rem;
    }

    .stat-card .stat-icon {
        top: 0.4rem;
        right: 0.45rem;
        font-size: 1.2rem;
    }

    .stat-card:hover {
        transform: none;
    }

    .page-header {
        margin-bottom: 1.25rem;
    }

    .page-header-inner {
        flex-direction: column;
        align-items: stretch;
    }

    .page-header h2 {
        font-size: 1.35rem;
    }

    .page-header p {
        font-size: 0.85rem;
    }

    .page-header-actions .btn {
        flex: 1 1 auto;
    }

    table {
        font-size: 0.85rem;
    }

    table th,
    table td {
        padding: 0.6rem 0.75rem;
    }

    .btn {
        padding: 0.5rem 1rem;
        font-size: 0.9rem;
    }

    .carga-errores {
        max-height: 160px;
    }
}

/* En un teléfono de verdad las tarjetas de dos columnas solo llevan etiqueta y
   número: el icono decorativo se quita para que quepa el texto. */
@media (max-width: 400px) {
    .stats-grid {
        grid-template-columns: repeat(2, 1fr);
    }

    .stat-card {
        padding: 0.7rem;
    }

    .stat-card .stat-icon {
        display: none;
    }

    .stat-card h3 {
        padding-right: 0;
        min-height: 2.1em;
    }

    .stat-card .stat-value {
        font-size: 1.6rem;
    }
}

/* ============================================
   Examina - Exercise Cards
   ============================================ */

.exercise-card {
    background: var(--bg-secondary);
    border-radius: var(--radius-lg);
    padding: 1.5rem;
    box-shadow: var(--shadow-sm);
    border: 1px solid var(--border-color);
    margin-bottom: 1rem;
    transition: var(--transition);
}

.exercise-card:hover {
    box-shadow: var(--shadow-md);
    transform: translateY(-2px);
}

.exercise-header {
    display: flex;
    justify-content: space-between;
    align-items: start;
    margin-bottom: 1rem;
}

.exercise-title {
    font-size: 1.25rem;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: 0.25rem;
}

.exercise-meta {
    display: flex;
    gap: 1rem;
    flex-wrap: wrap;
    margin-bottom: 1rem;
}

.meta-item {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    color: var(--text-secondary);
    font-size: 0.9rem;
}

.exercise-actions {
    display: flex;
    gap: 0.5rem;
    flex-wrap: wrap;
}

/* ============================================
   Examina - Question Builder
   ============================================ */

.question-block {
    background: var(--bg-secondary);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-lg);
    padding: 1.5rem;
    margin-bottom: 1rem;
}

.question-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 1rem;
}

.question-number {
    font-weight: 600;
    color: var(--accent-primary);
    font-size: 1.1rem;
}

.question-actions {
    display: flex;
    gap: 0.5rem;
}

.question-type-selector {
    display: flex;
    gap: 0.5rem;
    margin-bottom: 1rem;
    flex-wrap: wrap;
}

.type-option {
    padding: 0.5rem 1rem;
    border: 2px solid var(--border-color);
    border-radius: var(--radius-md);
    background: var(--bg-primary);
    cursor: pointer;
    transition: var(--transition);
    font-size: 0.9rem;
}

.type-option:hover {
    border-color: var(--accent-primary);
}

.type-option.active {
    border-color: var(--accent-primary);
    background: var(--accent-primary);
    color: white;
}

/* ============================================
   Examina - Progress Bar
   ============================================ */

.progress-bar {
    width: 100%;
    height: 8px;
    background: var(--bg-tertiary);
    border-radius: var(--radius-sm);
    overflow: hidden;
    margin: 1rem 0;
}

.progress-fill {
    height: 100%;
    background: linear-gradient(90deg, var(--accent-primary), var(--accent-secondary));
    transition: width 0.3s ease;
    border-radius: var(--radius-sm);
}

/* ============================================
   Examina - Status Badges
   ============================================ */

.badge {
    display: inline-flex;
    align-items: center;
    gap: 0.25rem;
    padding: 0.25rem 0.75rem;
    border-radius: var(--radius-sm);
    font-size: 0.85rem;
    font-weight: 500;
}

.badge-primary {
    background: rgba(59, 130, 246, 0.1);
    color: var(--accent-primary);
}

.badge-success {
    background: rgba(16, 185, 129, 0.1);
    color: var(--accent-success);
}

.badge-warning {
    background: rgba(245, 158, 11, 0.1);
    color: var(--accent-warning);
}

.badge-danger {
    background: rgba(239, 68, 68, 0.1);
    color: var(--accent-danger);
}

.badge-info {
    background: rgba(59, 130, 246, 0.1);
    color: var(--accent-primary);
}

.badge-secondary {
    background: var(--bg-tertiary);
    color: var(--text-secondary);
}

/* ============================================
   Examina - Recording Controls
   ============================================ */

.recording-controls {
    display: flex;
    gap: 1rem;
    align-items: center;
    justify-content: center;
    padding: 1rem;
    background: var(--bg-tertiary);
    border-radius: var(--radius-lg);
    margin: 1rem 0;
}

.record-btn {
    width: 60px;
    height: 60px;
    border-radius: 50%;
    border: none;
    background: var(--accent-danger);
    color: white;
    font-size: 1.5rem;
    cursor: pointer;
    transition: var(--transition);
    display: flex;
    align-items: center;
    justify-content: center;
}

.record-btn:hover {
    transform: scale(1.1);
}

.record-btn.recording {
    animation: pulse 1.5s infinite;
}

@keyframes pulse {
    0%, 100% { transform: scale(1); }
    50% { transform: scale(1.05); }
}

.recording-timer {
    font-size: 1.5rem;
    font-weight: 600;
    color: var(--text-primary);
    font-variant-numeric: tabular-nums;
}