/* ── Stale rider marker (ghost mode) ────────────────────────────────────── */
.rider-stale-marker {
    opacity: 0.5;
    filter: grayscale(70%);
}

/* ── SOS / lost-rider alarm pulse ───────────────────────────────────────── */
@keyframes sos-pulse {
    0%   { transform: scale(1);    filter: drop-shadow(0 0 0px #e74c3c); }
    50%  { transform: scale(1.55); filter: drop-shadow(0 0 8px #ff0000); }
    100% { transform: scale(1);    filter: drop-shadow(0 0 0px #e74c3c); }
}

.rider-sos-marker {
    animation: sos-pulse 0.9s ease-in-out infinite;
}