Make background images Responsive?

Hi,
I’m a newbie,
I’m making a folio site
I have some portrait and some landscape images.

  • Do I need to resize these to be correct ratio before I import or can a use The div box like a mask to crop?
    I know if I make the images background then it crops, but

  • how do you make background images responsive - so when scaled down for mobile etc it doesn’t get huge?

  • I’ve had success with responsive grid on another page (used grid / divbox / image in doc box (with div box as relative and image as absolute)

But now I have portrait images I want alongside landscape it’s getting very tricky!

Advice appreciated!
Thanks


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