/* Variables de paleta de colores pastel y tipografía */
:root {
    --bg-pastel-gray: #f4f6f6;
    --bg-white: #ffffff;
    --primary-pastel-blue: #d4e6f1;
    --primary-blue-dark: #2e4053;
    --accent-pastel-green: #d5f5e3;
    --accent-green-dark: #1e8449;
    --text-main: #34495e;
    --text-muted: #7f8c8d;
    --border-color: #e5e8e8;
    --footer-navy: #1b4f72;
}

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

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background-color: var(--bg-pastel-gray);
    color: var(--text-main);
    display: flex;
    flex-direction: column;
    min-height: 100vh;
}

.hidden {
    display: none !important;
}

/* Estilos de Modal de Registro */
.modal {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(46, 64, 83, 0.5);
    display: flex;
    justify-content: center;
    align-items: center;
    z-index: 1000;
}

.modal-content {
    background-color: var(--bg-white);
    padding: 30px;
    border-radius: 8px;
    box-shadow: 0 4px 15px rgba(0,0,0,0.1);
    width: 90%;
    max-width: 450px;
}

.modal-content h2 {
    color: var(--footer-navy);
    margin-bottom: 15px;
}

.form-group {
    margin-bottom: 15px;
}

.form-group label {
    display: block;
    margin-bottom: 5px;
    font-weight: 600;
    font-size: 0.9rem;
}

.form-group input {
    width: 100%;
    padding: 10px;
    border: 1px solid var(--border-color);
    border-radius: 4px;
    font-size: 1rem;
}

.form-group input[readonly] {
    background-color: var(--bg-pastel-gray);
    color: var(--text-muted);
}

/* Contenedor Grid Principal */
.app-container {
    display: grid;
    grid-template-columns: 280px 1fr 260px;
    gap: 20px;
    padding: 20px;
    flex: 1;
    max-width: 1600px;
    width: 100%;
    margin: 0 auto;
}

/* Columna Izquierda: Sidebar */
.sidebar-left {
    background-color: var(--bg-white);
    border-radius: 8px;
    padding: 20px;
    border: 1px solid var(--border-color);
    display: flex;
    flex-direction: column;
    gap: 20px;
}

.student-info-badge {
    background-color: var(--primary-pastel-blue);
    padding: 12px;
    border-radius: 6px;
    font-size: 0.85rem;
    color: var(--primary-blue-dark);
}

/* Medidor Gráfico de Progreso */
.progress-bar-wrapper {
    background-color: var(--bg-pastel-gray);
    border-radius: 10px;
    overflow: hidden;
    margin: 8px 0;
    border: 1px solid var(--border-color);
}

.progress-bar {
    width: 0%;
    background-color: #85c1e9;
    color: var(--primary-blue-dark);
    text-align: center;
    font-size: 0.75rem;
    font-weight: bold;
    padding: 4px 0;
    transition: width 0.4s ease;
}

.progress-text {
    font-size: 0.8rem;
    color: var(--text-muted);
}

/* Navegador del Estudiante */
.step-nav ul {
    list-style: none;
}

.nav-item {
    display: flex;
    align-items: center;
    gap: 10px;
    padding: 10px;
    border-radius: 6px;
    margin-bottom: 5px;
    cursor: pointer;
    transition: background-color 0.2s;
}

.nav-item:hover {
    background-color: var(--bg-pastel-gray);
}

.nav-item.active {
    background-color: var(--primary-pastel-blue);
    font-weight: 600;
}

.step-check {
    width: 16px;
    height: 16px;
    cursor: pointer;
}

.nav-item label {
    cursor: pointer;
    font-size: 0.9rem;
    flex: 1;
}

/* Columna Central: Contenido (Prioridad de Diseño) */
.content-center {
    background-color: var(--bg-white);
    border-radius: 8px;
    padding: 30px;
    border: 1px solid var(--border-color);
    box-shadow: 0 2px 5px rgba(0,0,0,0.02);
    display: flex;
    flex-direction: column;
}

.practice-section {
    display: none;
    flex-direction: column;
    gap: 15px;
    height: 100%;
}

.practice-section.active {
    display: flex;
}

.practice-section h2 {
    color: var(--footer-navy);
    border-bottom: 2px solid var(--primary-pastel-blue);
    padding-bottom: 8px;
}

/* Bloques de Código */
pre {
    background-color: #2c3e50;
    color: #ecf0f1;
    padding: 15px;
    border-radius: 6px;
    overflow-x: auto;
    font-family: 'Consolas', 'Courier New', Courier, monospace;
    font-size: 0.9rem;
    line-height: 1.4;
}

.scrollable-code-box {
    max-height: 450px;
    overflow-y: auto;
    border-radius: 6px;
    border: 1px solid var(--border-color);
}

.highlight {
    background-color: #fcf3cf;
    padding: 2px 6px;
    border-radius: 4px;
    font-family: monospace;
    font-weight: bold;
}

.instruction-note {
    background-color: #fef9e7;
    border-left: 4px solid #f4d03f;
    padding: 10px;
    font-size: 0.9rem;
    border-radius: 0 4px 4px 0;
}

/* Tablas de Datos */
.data-table {
    width: 100%;
    border-collapse: collapse;
    margin-top: 10px;
    font-size: 0.9rem;
}

.data-table th, .data-table td {
    border: 1px solid var(--border-color);
    padding: 10px;
    text-align: left;
}

.data-table th {
    background-color: var(--primary-pastel-blue);
    color: var(--primary-blue-dark);
}

.data-table tr:nth-child(even) {
    background-color: var(--bg-pastel-gray);
}

/* Flujo de Navegación Inferior */
.flow-navigation {
    margin-top: auto;
    padding-top: 25px;
    display: flex;
    justify-content: space-between;
}

/* Columna Derecha: Notas */
.sidebar-right {
    background-color: var(--bg-white);
    border-radius: 8px;
    padding: 20px;
    border: 1px solid var(--border-color);
    display: flex;
    flex-direction: column;
    gap: 12px;
}

.section-desc {
    font-size: 0.8rem;
    color: var(--text-muted);
}

#student-notes {
    width: 100%;
    flex: 1;
    min-height: 200px;
    padding: 12px;
    border: 1px solid var(--border-color);
    border-radius: 6px;
    resize: none;
    font-family: inherit;
    font-size: 0.9rem;
    background-color: #fefefe;
}

#student-notes:focus {
    outline: none;
    border-color: #85c1e9;
}

/* Botones Estilizados */
.btn-primary, .btn-secondary, .btn-success {
    padding: 10px 15px;
    border: none;
    border-radius: 4px;
    cursor: pointer;
    font-weight: 600;
    font-size: 0.9rem;
    transition: background-color 0.2s;
}

.btn-primary {
    background-color: #85c1e9;
    color: var(--primary-blue-dark);
}

.btn-primary:hover:not(:disabled) {
    background-color: #5dade2;
}

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

.btn-secondary:hover:not(:disabled) {
    background-color: #bdc3c7;
}

.btn-success {
    background-color: var(--accent-pastel-green);
    color: var(--accent-green-dark);
}

.btn-success:hover {
    background-color: #58d68d;
    color: white;
}

button:disabled {
    opacity: 0.5;
    cursor: not-allowed;
}

/* Footer Estilo Discreto Azul Marino */
footer {
    text-align: center;
    padding: 15px;
    margin-top: auto;
    background-color: var(--bg-white);
    border-top: 1px solid var(--border-color);
}

footer p {
    color: var(--footer-navy);
    font-size: 0.85rem;
    font-weight: 500;
}

/* Responsividad: Mobile First / Media Queries */
@media (max-width: 992px) {
    .app-container {
        grid-template-columns: 1fr;
        padding: 10px;
    }

    /* Orden en móviles requested: navegación arriba, contenido en medio, notas abajo */
    .sidebar-left {
        order: 1;
    }
    
    .content-center {
        order: 2;
        min-height: 400px;
    }

    .sidebar-right {
        order: 3;
    }

    #student-notes {
        min-height: 150px;
    }
}
.image-container {
    width: 100%;
    display: flex;
    justify-content: center;
    align-items: center;
    margin-top: 15px;
    padding: 5px;
    background-color: var(--bg-pastel-gray);
    border-radius: 6px;
    border: 1px dashed #bdc3c7; /* Delimita sutilmente el espacio de la futura imagen */
}

.practice-image {
    max-width: 100%;
    height: auto;
    border-radius: 4px;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.05);
    object-fit: contain;
    display: block;
    /* Suavizado en la carga */
    transition: opacity 0.3s ease-in-out;
}

/* Ajustes de visualización óptima en pantallas pequeñas */
@media (max-width: 992px) {
    .image-container {
        margin-top: 10px;
        padding: 2px;
    }
}