Variable layout with flex?

Ok, so I have either 1, 2 or 3 images that I want to display in a fixed height div.
I want the images to be as large as possible. The CMS will show the images.
Im sure I have done this before, but can’t figure it out this time! I have tried flex for this, but perhaps a grid is better?

28%20PM

59%20PM


Here is my site Read-Only: LINK

did you check the site link? it should go directly to the page. If not, its /test/test-flex

I think what you’re looking to achieve is here:

Plus this page can help a lot: