.mb-status {
  text-align: center;
  color: var(--text-muted);
  font-size: 0.92rem;
  margin: 0 0 16px;
  min-height: 1.3em;
}

.mb-slots {
  display: flex;
  justify-content: center;
  gap: 10px;
  flex-wrap: wrap;
  margin-bottom: 18px;
}
.mb-slot {
  width: 56px;
  height: 56px;
  border: 2px dashed var(--border-strong);
  border-radius: 10px;
  background: var(--bg-elevated);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.7rem;
  cursor: pointer;
}
.mb-slot.filled {
  border-style: solid;
  border-color: var(--accent);
  background: var(--cell-bg);
}

.mb-tray {
  display: flex;
  justify-content: center;
  gap: 10px;
  flex-wrap: wrap;
  margin-bottom: 18px;
  min-height: 60px;
}
.mb-tray-item {
  width: 56px;
  height: 56px;
  border: 1px solid var(--border-strong);
  border-radius: 10px;
  background: var(--bg-elevated);
  font-size: 1.7rem;
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  transition: transform 0.08s, opacity 0.12s;
}
.mb-tray-item:active { transform: scale(0.93); }
.mb-tray-item.used { opacity: 0.25; cursor: not-allowed; pointer-events: none; }

.actions-row {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  justify-content: center;
  max-width: 420px;
  margin: 0 auto 18px;
}

.mb-history {
  max-width: 420px;
  margin: 8px auto 0;
  display: flex;
  flex-direction: column;
  gap: 6px;
}
.mb-history-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 10px;
  background: var(--bg-elevated);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 6px 12px;
  font-size: 1rem;
}
.mb-history-row .seq { letter-spacing: 2px; }
.mb-history-row .fb {
  font-size: 0.82rem;
  font-weight: 700;
  color: var(--text-muted);
  white-space: nowrap;
}
.mb-history-row.solved .fb { color: var(--success); }