.hint { text-align: center; color: #64748B; font-size: 0.9rem; margin-bottom: 0.75rem; max-width: 320px; }
.lights-board { display: grid; grid-template-columns: repeat(5, 1fr); gap: 0.5rem; max-width: 320px; }
.light-cell { aspect-ratio: 1; border: none; border-radius: 12px; cursor: pointer; min-height: 44px; transition: transform 0.15s, box-shadow 0.15s; }
.light-cell.on { background: linear-gradient(135deg, #FDE68A, #FBBF24); box-shadow: 0 0 16px rgba(251, 191, 36, 0.7); }
.light-cell.off { background: #334155; box-shadow: inset 0 2px 6px rgba(0,0,0,0.4); }
.light-cell:hover { transform: scale(1.06); }