/* ======================================================= */
/* styles.css v2.0 - ARCHIVO CENTRALIZADO                 */
/* Contiene las variables de tema, idioma y diseño.       */
/* ======================================================= */

/*------------------------------------*\
 * VARIABLES DE COLOR (TEMAS)
\*------------------------------------*/

/* Tema Claro (Por defecto) */
:root {
    --bg-primary: #ffffff;
    --bg-secondary: #f8f9fa;
    --bg-header: linear-gradient(135deg, #1a4b8c 0%, #3179ac 100%);
    --bg-nav: #f8f9fa;
    --bg-content: #ffffff;
    --bg-nav-link: #ffffff;
    --bg-nav-link-hover: #1a4b8c;
    --bg-nav-link-active: #1a4b8c;
    
    --text-primary: #2d3748;
    --text-secondary: #4a5568;
    --text-header: #ffffff;
    --text-header-links: #a9d1ff;
    --text-header-links-hover: #ffffff;
    --text-nav-link: #1a4b8c;
    --text-nav-link-hover: #ffffff;
    --text-nav-link-active: #ffffff;
    --text-footer: #a9d1ff;
    --text-footer-hover: #ffffff;
    --text-highlight: #1a4b8c;
    
    --border-color: #e2e8f0;
    --border-highlight: #a9d1ff;
    --shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
    --shadow-hover: 0 8px 12px rgba(0, 0, 0, 0.2);
    --bg-footer: #2d3748;
    
    /* Estilos de Tabla */
    --table-header-bg: #1a4b8c;
    --table-header-text: #ffffff;
    --table-row-even-bg: #f7fafc;
    --table-row-hover-bg: #edf2f7;
    --table-link: #3179ac;
    --table-link-hover: #1a4b8c;
    --table-row-practice-bg: #fff9e6;
    --table-row-appendix-bg: #f0f9ff;
    
    /* Variables del CSS original (por si se usan) */
    --primary-blue: #1a4b8c;
    --secondary-blue: #3179ac;
    --light-blue: #a9d1ff;
    --background-gray: #f8f9fa;
    --text-dark: #2d3748;
    --text-light: #4a5568;
    --white: #ffffff;
    --border-radius: 8px;
    --transition: all 0.3s ease;
}

/* Tema Oscuro (Cuando data-theme="dark") */
[data-theme="dark"] {
    --bg-primary: #1a202c;
    --bg-secondary: #2d3748;
    --bg-header: linear-gradient(135deg, #1a4b8c 0%, #2d3748 100%);
    --bg-nav: #2d3748;
    --bg-content: #2d3748;
    --bg-nav-link: #4a5568;
    --bg-nav-link-hover: #a9d1ff;
    --bg-nav-link-active: #a9d1ff;

    --text-primary: #f7fafc;
    --text-secondary: #e2e8f0;
    --text-header: #ffffff;
    --text-header-links: #a9d1ff;
    --text-header-links-hover: #ffffff;
    --text-nav-link: #f7fafc;
    --text-nav-link-hover: #1a202c;
    --text-nav-link-active: #1a202c;
    --text-footer: #a9d1ff;
    --text-footer-hover: #ffffff;
    --text-highlight: #a9d1ff;

    --border-color: #4a5568;
    --border-highlight: #3179ac;
    --shadow: 0 4px 6px rgba(0, 0, 0, 0.3);
    --shadow-hover: 0 8px 12px rgba(0, 0, 0, 0.4);
    --bg-footer: #1a202c;

    /* Estilos de Tabla (Oscuro) */
    --table-header-bg: #3179ac;
    --table-header-text: #ffffff;
    --table-row-even-bg: #2d3748; /* Fondo principal oscuro */
    --table-row-hover-bg: #4a5568; /* Un poco más claro */
    --table-link: #a9d1ff;
    --table-link-hover: #ffffff;
    --table-row-practice-bg: #4a4431; /* Ocre oscuro */
    --table-row-appendix-bg: #314452; /* Azulado oscuro */
}

/*------------------------------------*\
 * ESTILOS BASE
\*------------------------------------*/
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
}

body {
    font-family: 'Inter', 'Segoe UI', system-ui, sans-serif;
    line-height: 1.6;
    background-color: var(--bg-primary);
    color: var(--text-primary);
    display: flex;
    flex-direction: column;
    min-height: 100vh;
    transition: background-color 0.3s ease, color 0.3s ease;
}

/*------------------------------------*\
 * CONTROLES (IDIOMA Y TEMA)
\*------------------------------------*/
.controls-container {
    position: absolute;
    top: 1rem;
    right: 1rem;
    display: flex;
    gap: 1rem;
    align-items: center;
    z-index: 10;
}

.lang-toggle button {
    background-color: rgba(255, 255, 255, 0.2);
    border: 1px solid var(--text-header-links);
    color: var(--text-header-links);
    padding: 0.3rem 0.6rem;
    cursor: pointer;
    font-weight: bold;
    transition: all 0.3s ease;
}
.lang-toggle button:first-child { border-radius: 5px 0 0 5px; }
.lang-toggle button:last-child { border-radius: 0 5px 5px 0; border-left: none; }

.lang-toggle button:hover,
.lang-toggle button.active {
    background-color: var(--text-header-links);
    color: var(--primary-blue); /* Color del fondo del header */
}

.theme-switch {
    display: inline-block;
    height: 26px;
    position: relative;
    width: 50px;
}
.theme-switch input { display: none; }
.theme-slider {
    background-color: rgba(255, 255, 255, 0.2);
    border: 1px solid var(--text-header-links);
    bottom: 0;
    cursor: pointer;
    left: 0;
    position: absolute;
    right: 0;
    top: 0;
    transition: .4s;
    border-radius: 26px;
}
.theme-slider:before {
    background-color: var(--text-header-links);
    bottom: 3px;
    content: "";
    height: 18px;
    width: 18px;
    left: 4px;
    position: absolute;
    transition: .4s;
    border-radius: 50%;
}
input:checked + .theme-slider {
    background-color: #3179ac;
}
input:checked + .theme-slider:before {
    transform: translateX(24px);
    background-color: white;
}

/*------------------------------------*\
 * LOGOS CORPORATIVOS
\*------------------------------------*/
.header-logos {
    display: flex;
    justify-content: center;
    align-items: center;
    gap: 2rem;
    padding-top: 1rem;
}
.header-logos .logo {
    height: 50px;
    width: auto;
    opacity: 0.9;
}
/* Fondo blanco para logos en modo oscuro */
[data-theme="dark"] .logo {
    background-color: white;
    padding: 4px;
    border-radius: 4px;
}

/*------------------------------------*\
 * HEADER
\*------------------------------------*/
.header {
    background: var(--bg-header);
    color: var(--text-header);
    padding: 2rem 1rem;
    box-shadow: var(--shadow);
    position: relative;
}

.header-content {
    max-width: 1200px;
    margin: 0 auto;
    text-align: center;
}

.university-links {
    margin-bottom: 1rem;
    font-size: 0.9rem;
}

.university-links a {
    color: var(--text-header-links);
    text-decoration: none;
    margin: 0 0.5rem;
    transition: all 0.3s ease;
}

.university-links a:hover {
    color: var(--text-header-links-hover);
    text-decoration: underline;
}

.course-title {
    font-size: 2.5rem;
    font-weight: 700;
    margin: 0.5rem 0;
    color: var(--text-header);
}
.course-subtitle, .course-meta {
    font-size: 1.2rem;
    font-weight: 400;
    opacity: 0.9;
    margin-bottom: 0.5rem;
}
.course-meta { font-size: 0.9rem; opacity: 0.8; }

/*------------------------------------*\
 * BARRA DE NAVEGACIÓN
\*------------------------------------*/
.nav-bar {
    background: var(--bg-nav);
    padding: 1rem 0;
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.05);
    border-bottom: 1px solid var(--border-color);
    transition: background-color 0.3s ease, border-color 0.3s ease;
    position: sticky; /* Menú fijo */
    top: 0;
    z-index: 5;
}
.nav-container { max-width: 1200px; margin: 0 auto; padding: 0 1rem; }
.nav-menu {
    display: flex;
    justify-content: center;
    list-style: none;
    flex-wrap: wrap;
    gap: 1rem;
}
.nav-item {
    margin: 0;
}
.nav-link {
    display: block;
    padding: 0.6rem 1.2rem;
    background: var(--bg-nav-link);
    color: var(--text-nav-link);
    text-decoration: none;
    border-radius: 8px;
    border: 2px solid transparent;
    transition: all 0.3s ease;
    font-weight: 500;
    font-size: 0.95rem;
}
.nav-link:hover {
    background: var(--bg-nav-link-hover);
    color: var(--text-nav-link-hover);
    border-color: var(--bg-nav-link-hover);
    transform: translateY(-2px);
}
.nav-link.active {
    background: var(--bg-nav-link-active);
    color: var(--text-nav-link-active);
    font-weight: bold;
}

/*------------------------------------*\
 * CONTENIDO PRINCIPAL
\*------------------------------------*/
.main-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 2rem 1rem;
    flex: 1;
}
.content {
    background: var(--bg-content);
    border-radius: 8px;
    padding: 2.5rem;
    box-shadow: var(--shadow);
    transition: background-color 0.3s ease;
}
.page-header {
    margin-bottom: 2.5rem;
    padding-bottom: 1rem;
    border-bottom: 2px solid var(--border-highlight);
    text-align: center;
}
.page-title {
    color: var(--text-highlight);
    font-size: 2.2rem;
    font-weight: 600;
    margin-bottom: 0.5rem;
}
.page-subtitle {
    color: var(--text-secondary);
    font-size: 1.1rem;
    line-height: 1.5;
}

.section { margin-bottom: 3rem; }
.section-title {
    color: var(--text-highlight);
    font-size: 1.8rem;
    font-weight: 600;
    margin-bottom: 1rem;
    padding-bottom: 0.5rem;
    border-bottom: 3px solid var(--border-highlight);
}
.section-content {
    color: var(--text-secondary);
    font-size: 1.1rem;
    line-height: 1.7;
}
.section-content p {
    margin-bottom: 1.2rem;
    text-align: justify;
}
.highlight { color: var(--text-highlight); font-weight: 500; }
.italic { font-style: italic; }

/*------------------------------------*\
 * FIGURAS E IMÁGENES
\*------------------------------------*/
.figure-container {
    display: flex;
    align-items: flex-start;
    gap: 2rem;
    margin: 2rem 0;
    flex-wrap: wrap;
}
.figure-image {
    flex: 0 0 250px;
    max-width: 100%;
    border-radius: 8px;
    overflow: hidden;
    box-shadow: var(--shadow);
    transition: all 0.3s ease;
}
.figure-image img { width: 100%; height: auto; display: block; }
.figure-image:hover {
    transform: scale(1.02);
    box-shadow: var(--shadow-hover);
}
.figure-caption {
    flex: 1;
    min-width: 300px;
    font-size: 0.9rem;
    color: var(--text-secondary);
    line-height: 1.5;
}

/*------------------------------------*\
 * ESTILOS DE TABLAS
\*------------------------------------*/
.materials-table,
.presentations-table {
    width: 100%;
    border-collapse: collapse;
    margin: 2rem 0;
    box-shadow: var(--shadow);
    border-radius: 8px;
    overflow: hidden; /* Para que el radius afecte a las esquinas */
}
.materials-table thead,
.presentations-table thead {
    background-color: var(--table-header-bg);
    color: var(--table-header-text);
}
.materials-table th,
.presentations-table th {
    padding: 1.2rem 1rem;
    text-align: left;
    font-weight: 600;
    font-size: 0.9rem;
    text-transform: uppercase;
    letter-spacing: 0.5px;
}
.materials-table tbody tr,
.presentations-table tbody tr {
    transition: background-color 0.3s ease;
}
.materials-table tbody tr:nth-child(even),
.presentations-table tbody tr:nth-child(even) {
    background-color: var(--table-row-even-bg);
}
.materials-table tbody tr:hover,
.presentations-table tbody tr:hover {
    background-color: var(--table-row-hover-bg);
}
.materials-table td,
.presentations-table td {
    padding: 1.2rem 1rem;
    border-bottom: 1px solid var(--border-color);
    vertical-align: top;
    color: var(--text-secondary);
}
.material-ref,
.presentation-number {
    font-weight: 600;
    color: var(--text-highlight);
    text-align: center;
    width: 10%;
}
.presentation-number { width: 5%; }
.material-link,
.presentation-link {
    color: var(--table-link);
    text-decoration: none;
    font-weight: 500;
    transition: all 0.3s ease;
    display: inline-block;
    padding: 0.2rem 0;
}
.material-link:hover,
.presentation-link:hover {
    color: var(--table-link-hover);
    text-decoration: underline;
    transform: translateX(2px);
}
.material-description,
.presentation-description {
    line-height: 1.5;
    color: var(--text-secondary); /* Asegura que el texto de la tabla herede el color */
}
.material-date,
.presentation-date {
    font-size: 0.9rem;
    white-space: nowrap;
    width: 15%;
    color: var(--text-secondary);
}
.practice-row {
    background-color: var(--table-row-practice-bg) !important;
    font-weight: 500; /* Un poco menos fuerte que bold */
}
.appendix-row {
    background-color: var(--table-row-appendix-bg) !important;
    font-style: italic;
}
.part-row {
    background-color: var(--table-row-even-bg) !important;
    font-weight: bold;
}
[data-theme="dark"] .part-row {
     background-color: var(--table-row-hover-bg) !important;
}

/*------------------------------------*\
 * FOOTER Y CONTADOR
\*------------------------------------*/
.footer {
    background: var(--bg-footer);
    color: var(--text-footer);
    text-align: center;
    padding: 1.5rem;
    margin-top: auto;
    transition: background-color 0.3s ease;
}
.footer a {
    color: var(--text-footer);
    text-decoration: none;
}
.footer a:hover {
    color: var(--text-footer-hover);
    text-decoration: underline;
}
.page-counter {
    margin-top: 1rem;
    font-size: 0.9rem;
    opacity: 0.7;
}

/*------------------------------------*\
 * LÓGICA DE IDIOMA (CSS) - CORREGIDA
\*------------------------------------*/

/* Por defecto (body lang="es"), ocultar inglés */
body[lang="es"] [lang="en"] { display: none; }

/* Cuando el body tenga lang="en", mostrar inglés y ocultar español */
body[lang="en"] [lang="en"] { display: inline; }
body[lang="en"] [lang="es"] { display: none; }

/* Ajustes para elementos que deben ser bloques (en ambos idiomas) */
body[lang="en"] .section-content p[lang="en"],
body[lang="en"] .figure-caption p[lang="en"],
body[lang="en"] .page-subtitle[lang="en"],
body[lang="en"] .course-subtitle[lang="en"],
body[lang="en"] .course-meta[lang="en"],
body[lang="en"] .nav-link span[lang="en"],
body[lang="en"] .footer p span[lang="en"],
body[lang="en"] .page-counter span[lang="en"],
body[lang="en"] .material-description[lang="en"],
body[lang="en"] .presentation-description[lang="en"],

body[lang="es"] .section-content p[lang="es"],
body[lang="es"] .figure-caption p[lang="es"],
body[lang="es"] .page-subtitle[lang="es"],
body[lang="es"] .course-subtitle[lang="es"],
body[lang="es"] .course-meta[lang="es"],
body[lang="es"] .nav-link span[lang="es"],
body[lang="es"] .footer p span[lang="es"],
body[lang="es"] .page-counter span[lang="es"],
body[lang="es"] .material-description[lang="es"],
body[lang="es"] .presentation-description[lang="es"]
{
    display: block;
}

/*------------------------------------*\
 * DISEÑO RESPONSIVO
\*------------------------------------*/
@media (max-width: 768px) {
    .main-container { padding: 1rem; }
    .course-title { font-size: 2rem; }
    /* Más padding top para controles */
    .header { padding: 4.5rem 1rem 1.5rem 1rem; } 
    .content { padding: 1.5rem; }
    .nav-menu { flex-direction: column; align-items: center; gap: 0.5rem; }
    .nav-item { width: 100%; max-width: 300px; }
    .nav-link { text-align: center; padding: 0.8rem; }
    .figure-container { flex-direction: column; }
    .figure-image { max-width: 300px; margin: 0 auto; }
    
    .controls-container {
        position: absolute;
        top: 1rem;
        right: 0.5rem;
        left: 0.5rem;
        flex-direction: row;
        justify-content: space-between;
        gap: 0.5rem;
        padding-bottom: 1rem;
        align-items: center;
    }
    .header-logos { padding-top: 0; }
    
    /* Tablas responsivas */
    .materials-table,
    .presentations-table {
        display: block;
        overflow-x: auto;
        white-space: nowrap; /* Evita que el texto se rompa */
    }
    .materials-table th, .materials-table td,
    .presentations-table th, .presentations-table td {
        padding: 0.8rem 0.5rem;
        font-size: 0.85rem;
        white-space: normal; /* Permite que el texto se rompa */
    }
    .material-description, .presentation-description {
        min-width: 300px; /* Ancho mínimo para descripción */
    }
}

/* Estilos extra del CSS original */
@media (max-width: 480px) {
    .course-title {
        font-size: 1.6rem;
    }

    .page-title {
        font-size: 1.5rem;
    }

    .university-links {
        display: flex;
        flex-direction: column;
        gap: 0.5rem;
    }
}

/* Accessibility */
@media (prefers-reduced-motion: reduce) {
    * {
        transition: none !important;
    }
}

.sr-only {
    position: absolute;
    width: 1px;
    height: 1px;
    padding: 0;
    margin: -1px;
    overflow: hidden;
    clip: rect(0, 0, 0, 0);
    white-space: nowrap;
    border: 0;
}