.target { text-align: center; margin-bottom: 18px; }
.target-num { font-size: clamp(2.6rem, 10vw, 4rem); font-weight: 700; color: var(--accent); line-height: 1.1; }

.cells { display: flex; justify-content: center; gap: clamp(4px, 1.6vw, 14px); flex-wrap: nowrap; margin: 8px 0 18px; }

.cell { display: flex; flex-direction: column; align-items: center; gap: 6px; min-width: 0; }
.cell .weight { font-family: var(--mono); font-size: clamp(0.72rem, 2.4vw, 0.9rem); font-weight: 700; color: var(--muted); }
.cell .power { font-size: 0.72rem; color: var(--muted); }
.cell .digit { font-family: var(--mono); font-weight: 700; font-size: 1.1rem; }

/* Bóng đèn (hệ 2) */
.bulb {
  width: clamp(32px, 9vw, 58px); aspect-ratio: 1; border-radius: 50%;
  border: 2px solid var(--border); background: var(--bit-off); cursor: pointer;
  transition: background 0.15s, box-shadow 0.2s, transform 0.08s; position: relative;
}
.bulb:active { transform: scale(0.94); }
.bulb.on { background: radial-gradient(circle at 35% 30%, #fff7d1, var(--bit-on) 60%); border-color: var(--bit-on); box-shadow: 0 0 18px 4px var(--bit-on-glow); }
.bulb:focus-visible { outline: 3px solid var(--accent); outline-offset: 3px; }
.cell.hint .bulb, .cell.hint .wheel { outline: 3px dashed var(--good); outline-offset: 4px; }

/* Bánh xe (hệ 8/16) */
.wheel { display: flex; flex-direction: column; align-items: center; border: 2px solid var(--border); border-radius: 14px; background: var(--surface-2); overflow: hidden; }
.wheel button { border: 0; background: transparent; color: var(--muted); width: 100%; padding: 4px 18px; cursor: pointer; font-size: 0.9rem; }
.wheel button:hover { color: var(--accent); background: var(--accent-soft); }
.wheel .face { font-family: var(--mono); font-size: 2.2rem; font-weight: 700; padding: 2px 16px; color: var(--accent); user-select: none; cursor: ns-resize; min-width: 64px; text-align: center; }

.readout { text-align: center; }
.repr { font-family: var(--mono); font-size: 1.3rem; font-weight: 700; letter-spacing: 0.08em; }
.sum { color: var(--muted); margin-top: 4px; min-height: 1.5em; }
.sum b { color: var(--text); font-family: var(--mono); }
.sum.match b { color: var(--good); }
.expansion { font-family: var(--mono); font-size: 0.92rem; }

@media (max-width: 420px) {
  .cell .power { display: none; }
  .wheel .face { font-size: 1.8rem; min-width: 52px; padding: 2px 10px; }
}