:root {
    --blue-900: #121a77;
    --blue-700: #1E2DBF;
    --orange-500: #EA580C;
    --white: #ffffff;
    --gray-200: #e5e7eb;
    --shadow-md: 0 3px 6px rgba(0, 0, 0, 0.08);
}

/*  Botón base (oculto en escritorio) */
.btn-back-mobile {
    display: none;
    position: absolute;
    /*  anclado al navbar */
    top: 50%;
    /* centrado verticalmente */
    right: 1rem;
    transform: translateY(-50%);
    /* corrige el centrado */
    z-index: 50;

    background-color: var(--white);
    color: var(--blue-900);
    border: 1px solid var(--gray-200);
    border-radius: 8px;
    padding: 0.4rem 0.6rem;
    font-size: 1rem;
    font-weight: 600;
    box-shadow: var(--shadow-md);
    cursor: pointer;
    transition: all 0.25s ease-in-out;
}

/* Icono dentro del botón */
.btn-back-mobile i {
    font-size: 1rem;
    line-height: 1;
}

/* Efectos visuales */
.btn-back-mobile:hover {
    background-color: var(--blue-900);
    color: var(--white);
    border-color: var(--blue-900);
    transform: translateY(-50%) scale(1.05);
}

.btn-back-mobile:active {
    transform: translateY(-50%) scale(0.97);
}

/* Mostrar y ajustar solo en pantallas móviles */
@media (max-width: 992px) {
    .navbar {
        position: relative;
        z-index: 100;
    }

    .btn-back-mobile {
        display: flex;
        justify-content: center;
        align-items: center;
    }
}

/*  Modo navbar oscuro (opcional) */
.navbar-dark .btn-back-mobile {
    background-color: var(--blue-900);
    color: var(--white);
    border-color: var(--blue-900);
}

.navbar-dark .btn-back-mobile:hover {
    background-color: var(--blue-700);
}