/* Estilos Base Universales */
body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    line-height: 1.6;
    color: #333;
    background-color: #f4f7f6;
    margin: 0;
    padding: 0;
}

header {
    background-color: #1e3a8a;
    color: white;
    padding: 2rem 1rem;
    text-align: center;
}

.container {
    max-width: 800px;
    margin: 2rem auto;
    padding: 0 1rem;
}

/* --- ESTILOS DEL ÍNDICE PRINCIPAL --- */
.grid-modelos {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 1.5rem;
    margin-top: 2rem;
}

.card-modelo {
    background: white;
    padding: 1.5rem;
    border-radius: 8px;
    box-shadow: 0 4px 6px rgba(0,0,0,0.05);
    text-align: center;
    border: 1px solid #e5e7eb;
}

.card-modelo h3 {
    margin-top: 0;
    color: #1e3a8a;
}

/* Botones */
.btn {
    display: inline-block;
    padding: 0.6rem 1.2rem;
    background-color: #3b82f6;
    color: white;
    text-decoration: none;
    border-radius: 6px;
    font-weight: 500;
    transition: background 0.2s;
}

.btn:hover {
    background-color: #1d4ed8;
}

/* --- NUEVO BOTÓN VOLVER AL ÍNDICE --- */
.btn-regresar {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.75rem 1.2rem;
    background-color: #ffffff;
    color: #1e3a8a; /* Color azul a juego con el encabezado */
    text-decoration: none;
    border-radius: 8px;
    font-weight: 600;
    font-size: 0.95rem;
    border: 2px solid #e5e7eb;
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.04);
    margin-bottom: 2rem;
    transition: all 0.2s ease-in-out;
}

/* Efecto al pasar el mouse (o tocar en el celular) */
.btn-regresar:hover {
    background-color: #1e3a8a;
    color: #ffffff;
    border-color: #1e3a8a;
    box-shadow: 0 4px 12px rgba(30, 58, 138, 0.2);
    transform: translateY(-2px); /* Pequeño salto hacia arriba */
}

/* Animación sutil de la flecha */
.btn-regresar .arrow {
    font-size: 1.2rem;
    transition: transform 0.2s ease;
}

.btn-regresar:hover .arrow {
    transform: translateX(-4px); /* La flecha se mueve a la izquierda al hacer hover */
}


/* --- ESTILOS DE LOS PASOS (GUIAS) --- */
.step-card {
    background: white;
    border-radius: 8px;
    box-shadow: 0 4px 6px rgba(0,0,0,0.1);
    margin-bottom: 2rem;
    padding: 1.5rem;
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
}

@media (min-width: 600px) {
    .step-card {
        flex-direction: row;
        align-items: center;
    }
}

.step-text {
    flex: 1;
}

.step-number {
    display: inline-block;
    background-color: #3b82f6;
    color: white;
    padding: 0.25rem 0.75rem;
    border-radius: 50px;
    font-weight: bold;
    font-size: 0.9rem;
    margin-bottom: 0.5rem;
}

.step-text h2 {
    margin: 0 0 0.5rem 0;
    color: #1e3a8a;
}

.step-image {
    flex: 1;
    text-align: center;
}

.step-image img {
    max-width: 100%;
    height: auto;
    border-radius: 6px;
    border: 1px solid #e5e7eb;
}

.note {
    background-color: #fef3c7;
    border-left: 4px solid #f59e0b;
    padding: 1rem;
    border-radius: 0 4px 4px 0;
    margin-top: 1rem;
}