The water is inside the screen and it may already be permanently damaged. There's no simple at-home solution to this. Best thing you can hope for is to find someone in your area with a vacuum dehydrator big enough to hold your laptop. Once inside, the vacuum will lower the boiling point, "cold-boil" the water, and then the dehydrator will remove the resulting vapor. But even this process may damage the screen. I think no matter what, you may ultimately have to replace the screen.