Gray and blue colour shades aren't correct after liquid spill?

I had a liquid spill (milk) accident on my MacBook Pro in which i unscrewed everything right after and cleaned all parts with alcohol then put it back together... everything seems fine except some weird vertical tiny yellow shades on the screen, and they change place when the viewed shape on the screen changes... so it's not the screen i guess, it's the graphics chip??

it's just that certain shades of gray look yellow on my screen and it's annoying, alongside with the very first gray apple screen (when you turn on your MacBook Pro) it doesn't look yellow, it just flickers. So what have I done wrong? didn't clean enough? didn't put everything back in place? the cables got harmed?

any thought would help, thank you all.