🎯 Goal

Divide the grid into white islands and a black sea. Each numbered cell is the seed of a white island — paint everything else black.

📏 The Rules

• Each number = a white island of exactly that many connected cells.
• Every island must contain exactly one number.
• Islands may not share an edge with another island. Corner-touching diagonally is fine — those are still separate islands.
• All black cells must form one connected sea.
• No 2×2 block of black cells anywhere.

✏️ Controls

• Tap any empty cell → paints it ⬛ Sea (black).
• Tap a Sea cell → converts it to ⬜ Island marker (purple dot).
• Tap an Island marker → clears it back to empty.
• Drag to paint multiple cells at once — all cells in the drag take the same state.
• Numbered cells are always white — you can't change them.
• 💡 Hint reveals whether one cell should be black or white.

💡 Strategy Tips

• A 1-island is just the number itself — all its neighbours must be black.
• Two numbers that are adjacent must belong to different islands, so there must be a black cell between their islands.
• Any cell that can't belong to any island must be black.
• Any 2×2 area — if 3 cells must be black, the 4th must be white.