.board-row {
  display: contents;
}

.board-row:last-child .cell {
  border-bottom: 0;
}

.easy {
  background: #137a3c;
}

.hard {
  background: #9c4f0d;
}

.number:disabled {
  cursor: default;
  opacity: .28;
}

.cell[aria-invalid="true"] {
  background: var(--error);
  color: var(--error-text);
}

.screen[aria-hidden="true"] {
  display: none;
}

@media (forced-colors: active) {
  .cell.selected {
    outline: 3px solid Highlight;
    outline-offset: -3px;
  }

  .cell.wrong {
    outline: 3px solid LinkText;
    outline-offset: -3px;
  }
}