How to resize image in flex-grow zone ?

[Warrangel]

Hey,

The goal of my project is to have a non-scrollable page.
I need to resize my image in a flex-grow area but the height of the image is kept when the area shrinks so the scroll is visible and when the area is enlarged, it's ok. I can't fixe my area because the area above is dynamic.

The problem exists for portrait images...

I share with you an explanatory diagram :

Thank you !!!

[ghost]

https://getbootstrap.com/docs/5.1/content/images/#responsive-images

Did you checked this out?

[Warrangel]

i have already this class on my picture :/ .... so i think it's due to my parent who is in flex-grow and therefore not a 'fixed' size ... because if I add a height on my zone it works fine.