iphone screen stain (behind screen

hi,

I would like to have some help on this problem

i got this weird problem since a few days.

my screen shows a big green stain (on a black background) but when i take a screenshot it's not there. It seems that when the screen is hot the green stain becomes more visible. i think it's a water problem but before i take the iphone apart i would like to know the exact problem...

thanks in advandce!

Everythingzen

got it second hand ...
when i don't use the iphone for like 45 minutes the big green stain disappears..
got some stain in the left corner as well that comes and goes also depending on phone use.

thanks for the help already!

Gonna replace the screen for 70 euro. Seems to be the only solution...