/**
 * BACK TO TOP — Botón "Volver arriba"
 * Aparece con .is-visible tras ~400px de scroll (JS). Fixed bottom-right.
 */

.informe-back-to-top {
    position: fixed;
    bottom: var(--space-6, 24px);
    right: var(--space-6, 24px);
    width: 48px;
    height: 48px;
    background: var(--color-brand-primary, #FF5920);
    color: #fff;
    border: none;
    border-radius: 50%;
    cursor: pointer;
    display: none;
    align-items: center;
    justify-content: center;
    font-size: 1.25rem;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.2);
    transition: background-color 0.3s ease, transform 0.3s ease, box-shadow 0.3s ease;
    z-index: 9999;
}

.informe-back-to-top.is-visible {
    display: flex;
}

.informe-back-to-top:hover {
    background: var(--color-brand-primary-dark, #cc4719);
    transform: translateY(-4px);
    box-shadow: 0 6px 16px rgba(0, 0, 0, 0.3);
}

.informe-back-to-top:active {
    transform: translateY(0);
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.2);
}

.informe-back-to-top:focus {
    outline: none;
}

.informe-back-to-top:focus-visible {
    outline: 3px solid var(--color-brand-primary, #FF5920);
    outline-offset: 4px;
}

@media (max-width: 768px) {
    .informe-back-to-top {
        width: 44px;
        height: 44px;
        bottom: var(--space-5, 20px);
        right: var(--space-5, 20px);
        font-size: 1.125rem;
    }
}

@keyframes informe-back-to-top-fadeIn {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.informe-back-to-top.is-visible {
    animation: informe-back-to-top-fadeIn 0.3s ease forwards;
}