Visible lines suddenly appeared on my Mac screen

Hello everyone m, 3 days ago I was watching YouTube on my Mac and suddenly horizontal and vertical lines appeared on my screen. The screen is not broken, so I suspect that water might have gotten through the trackpad while I was cooking, I am talking here about little drops. I putted my Mac upside down in a bag full of rice but problem persists. Can anyone help me understand what’s going on. Thank you.