Yin-Yang Killer

Normal sudoku rules apply.

Shade some cells such that all shaded cells are orthogonally connected and all unshaded cells are orthogonally connected and no 2x2 area may be fully shaded or unshaded.

Digits in cages may not repeat and sum to the given number. In these cages, shaded digits count as positive numbers, and unshaded digits count as negative numbers. Cages with no total sum to 0.

All unshaded digits in each cage are orthogonally connected.

The digit in the gray square is even.