html, body { margin: 0; height: 100%; overflow: hidden; background: #000; font-family: system-ui, -apple-system, "Segoe UI", sans-serif; }
#hint, #error {
  position: fixed; left: 50%; bottom: 28px; transform: translateX(-50%); z-index: 10;
  padding: 12px 18px; border-radius: 999px; max-width: 85vw; text-align: center;
  background: #ffdc00; color: #111; font-size: 15px; box-shadow: 0 4px 18px rgba(0,0,0,.35);
  transition: opacity .3s;
}
#hint.hidden { opacity: 0; }
#error { bottom: auto; top: 20px; background: #b00020; color: #fff; border-radius: 10px; }