#hint {
  position: fixed;
  left: 16px;
  bottom: 16px;
  right: 96px;
  max-width: 420px;
  z-index: 10;
  font: 14px/1.45 system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: 10px;
  padding: 10px 14px;
  opacity: 0;
  transition: opacity .6s;
  pointer-events: none;
}

#hint.show { opacity: 1; }
#hint b { font-weight: 600; }
#hint span { color: var(--muted); }