/* Shared mobile grid: two vertical guides across every visible section. */
@media (max-width: 575.8px) {
    .vertical-grid::before,
    .vertical-grid::after {
        display: block;
        width: 0;
        border-right: 0;
        border-left: 1px solid var(--vertical-grid-line-color);
    }

    .vertical-grid::before {
        left: calc(100% / 3);
    }

    .vertical-grid::after {
        left: calc(200% / 3);
    }
}