/* ── Screen navigation (phone layout) ───────────────────────────────── */
.screen-nav {
    display: none;
    grid-template-columns: repeat(3, 1fr);
    position: fixed;
    left: 0; right: 0; bottom: 0;
    height: var(--screen-nav-h);
    padding: 0 env(safe-area-inset-right, 0px) env(safe-area-inset-bottom, 0px) env(safe-area-inset-left, 0px);
    background: var(--surface);
    border-top: 1px solid var(--border);
    z-index: 100;
}
.screen-nav__item {
    border: 0;
    background: none;
    color: var(--text-muted);
    font: 600 var(--text-xs) var(--font-ui);
    letter-spacing: 0.06em;
    text-transform: uppercase;
    transition: color var(--tr), box-shadow var(--tr);
}
.screen-nav__item[aria-current="page"] {
    color: var(--gold);
    box-shadow: inset 0 2px 0 var(--gold);
}