/* ============================================
   RESET Y VARIABLES GLOBALES
   ============================================ */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

:root {
    /* Colores principales */
    --color-primario: #667eea;
    --color-secundario: #764ba2;
    --color-exito: #28a745;
    --color-peligro: #dc3545;
    --color-advertencia: #ffc107;
    --color-info: #17a2b8;
    
    /* Colores de fondo */
    --bg-principal: #f8f9fa;
    --bg-blanco: #ffffff;
    --bg-oscuro: #343a40;
    
    /* Colores de texto */
    --texto-principal: #212529;
    --texto-secundario: #6c757d;
    --texto-claro: #ffffff;
    
    /* Sombras */
    --sombra-suave: 0 2px 8px rgba(0,0,0,0.1);
    --sombra-media: 0 4px 12px rgba(0,0,0,0.15);
    --sombra-fuerte: 0 8px 24px rgba(0,0,0,0.2);
    
    /* Bordes */
    --radio-border: 12px;
    --radio-border-sm: 8px;
    
    /* Transiciones */
    --transicion: all 0.3s ease;
}

/* ============================================
   ESTILOS GENERALES
   ============================================ */
body {
    font-family: 'Poppins', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    background: linear-gradient(135deg, var(--color-primario) 0%, var(--color-secundario) 100%);
    background-attachment: fixed;
    color: var(--texto-principal);
    line-height: 1.6;
    min-height: 100vh;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

/* ============================================
   HEADER PRINCIPAL
   ============================================ */
.header-principal {
    background: var(--bg-blanco);
    box-shadow: var(--sombra-media);
    position: sticky;
    top: 0;
    z-index: 1000;
}

.header-content {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1rem 0;
}

/* Logo */
.logo {
    display: flex;
    align-items: center;
    gap: 10px;
    text-decoration: none;
    color: var(--texto-principal);
    font-weight: 600;
    font-size: 1.5rem;
    transition: var(--transicion);
}

.logo:hover {
    transform: scale(1.05);
}

.logo-icon {
    font-size: 2rem;
}

/* Navegación */
.nav-principal ul {
    display: flex;
    list-style: none;
    gap: 2rem;
}

.nav-link {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    text-decoration: none;
    color: var(--texto-secundario);
    font-weight: 500;
    transition: var(--transicion);
    padding: 0.5rem 1rem;
    border-radius: var(--radio-border-sm);
}

.nav-link:hover {
    background: var(--bg-principal);
    color: var(--color-primario);
}

/* Botón menú móvil */
.btn-menu-movil {
    display: none;
    flex-direction: column;
    gap: 5px;
    background: none;
    border: none;
    cursor: pointer;
    padding: 5px;
}

.btn-menu-movil span {
    width: 25px;
    height: 3px;
    background: var(--texto-principal);
    border-radius: 2px;
    transition: var(--transicion);
}

/* ============================================
   MAIN CONTENT
   ============================================ */
.main-content {
    min-height: calc(100vh - 200px);
    padding: 3rem 0;
}

/* ============================================
   HERO SECTION (Página principal)
   ============================================ */
.hero-section {
    text-align: center;
    margin-bottom: 4rem;
    color: var(--texto-claro);
}

.hero-section h1 {
    font-size: 3rem;
    font-weight: 700;
    margin-bottom: 1rem;
    text-shadow: 0 2px 10px rgba(0,0,0,0.2);
}

.hero-section p {
    font-size: 1.2rem;
    opacity: 0.9;
}

/* ============================================
   GRID DE CATEGORÍAS
   ============================================ */
.categorias-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 2rem;
    margin-bottom: 3rem;
}

.categoria-card {
    background: var(--bg-blanco);
    border-radius: var(--radio-border);
    padding: 2rem;
    text-align: center;
    text-decoration: none;
    color: var(--texto-principal);
    box-shadow: var(--sombra-suave);
    transition: var(--transicion);
    cursor: pointer;
    position: relative;
    overflow: hidden;
}

.categoria-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 5px;
    background: linear-gradient(90deg, var(--color-primario), var(--color-secundario));
    transform: scaleX(0);
    transition: var(--transicion);
}

.categoria-card:hover::before {
    transform: scaleX(1);
}

.categoria-card:hover {
    transform: translateY(-10px);
    box-shadow: var(--sombra-fuerte);
}

.categoria-icon {
    font-size: 4rem;
    margin-bottom: 1rem;
    display: block;
}

.categoria-card h3 {
    font-size: 1.5rem;
    margin-bottom: 0.5rem;
    color: var(--texto-principal);
}

.categoria-card p {
    color: var(--texto-secundario);
    font-size: 0.9rem;
}

.categoria-stats {
    margin-top: 1rem;
    padding-top: 1rem;
    border-top: 1px solid var(--bg-principal);
    font-size: 0.85rem;
    color: var(--texto-secundario);
}

/* ============================================
   BREADCRUMB (Migas de pan)
   ============================================ */
.breadcrumb {
    background: var(--bg-blanco);
    padding: 1rem 1.5rem;
    border-radius: var(--radio-border);
    margin-bottom: 2rem;
    box-shadow: var(--sombra-suave);
}

.breadcrumb ul {
    display: flex;
    list-style: none;
    flex-wrap: wrap;
    gap: 0.5rem;
}

.breadcrumb li {
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.breadcrumb a {
    color: var(--color-primario);
    text-decoration: none;
    transition: var(--transicion);
}

.breadcrumb a:hover {
    text-decoration: underline;
}

/* ============================================
   TARJETA DE TEMA COMPLETO
   ============================================ */
.tema-detalle {
    background: var(--bg-blanco);
    border-radius: var(--radio-border);
    padding: 3rem;
    box-shadow: var(--sombra-media);
}

.tema-header {
    text-align: center;
    margin-bottom: 3rem;
    padding-bottom: 2rem;
    border-bottom: 2px solid var(--bg-principal);
}

.tema-header h1 {
    font-size: 2.5rem;
    margin-bottom: 1rem;
    color: var(--color-primario);
}

.tema-descripcion {
    font-size: 1.1rem;
    color: var(--texto-secundario);
}

/* Preguntas y respuestas */
.pregunta-item {
    background: var(--bg-principal);
    border-radius: var(--radio-border);
    padding: 2rem;
    margin-bottom: 1.5rem;
    transition: var(--transicion);
}

.pregunta-item:hover {
    box-shadow: var(--sombra-suave);
}

.pregunta-titulo {
    font-size: 1.3rem;
    font-weight: 600;
    color: var(--color-primario);
    margin-bottom: 1rem;
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.pregunta-respuesta {
    font-size: 1.05rem;
    line-height: 1.8;
    color: var(--texto-principal);
}

.pregunta-respuesta ul {
    list-style: none;
    padding-left: 0;
}

.pregunta-respuesta ul li {
    padding: 0.5rem 0;
    padding-left: 1.5rem;
    position: relative;
}

.pregunta-respuesta ul li::before {
    content: '✓';
    position: absolute;
    left: 0;
    color: var(--color-exito);
    font-weight: bold;
}

.pregunta-fuente {
    margin-top: 1rem;
    font-size: 0.85rem;
    color: var(--texto-secundario);
    font-style: italic;
}

/* ============================================
   BOTONES
   ============================================ */
.btn {
    display: inline-block;
    padding: 0.75rem 1.5rem;
    border-radius: var(--radio-border-sm);
    text-decoration: none;
    font-weight: 500;
    transition: var(--transicion);
    cursor: pointer;
    border: none;
    font-size: 1rem;
}

.btn-primary {
    background: linear-gradient(135deg, var(--color-primario), var(--color-secundario));
    color: var(--texto-claro);
}

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

.btn-secondary {
    background: var(--bg-principal);
    color: var(--texto-principal);
}

.btn-secondary:hover {
    background: var(--texto-secundario);
    color: var(--texto-claro);
}

/* ============================================
   FOOTER
   ============================================ */
.footer-principal {
    background: var(--bg-blanco);
    margin-top: 4rem;
    padding: 3rem 0 1rem;
    box-shadow: 0 -2px 10px rgba(0,0,0,0.1);
}

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

.footer-section h3,
.footer-section h4 {
    margin-bottom: 1rem;
    color: var(--color-primario);
}

.footer-links {
    list-style: none;
}

.footer-links li {
    margin-bottom: 0.5rem;
}

.footer-links a {
    color: var(--texto-secundario);
    text-decoration: none;
    transition: var(--transicion);
}

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

.footer-stats {
    list-style: none;
}

.footer-stats li {
    margin-bottom: 0.5rem;
    color: var(--texto-secundario);
}

.footer-bottom {
    text-align: center;
    padding-top: 2rem;
    border-top: 1px solid var(--bg-principal);
    color: var(--texto-secundario);
}

/* ============================================
   RESPONSIVE DESIGN
   ============================================ */
@media (max-width: 768px) {
    .hero-section h1 {
        font-size: 2rem;
    }
    
    .categorias-grid {
        grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
        gap: 1rem;
    }
    
    .nav-principal {
        display: none;
    }
    
    .btn-menu-movil {
        display: flex;
    }
    
    .tema-detalle {
        padding: 1.5rem;
    }
    
    .pregunta-item {
        padding: 1.5rem;
    }
}

@media (max-width: 480px) {
    .categorias-grid {
        grid-template-columns: 1fr;
    }
    
    .categoria-icon {
        font-size: 3rem;
    }
}