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are flex container does not support position for cards?
I set justify content : right for flex container, but cards does not move to the right side.
demo: https://we.tl/t-ew7pxlK1Mp

The implementation of your card layout is wrong.
The max-width in combination with flex-grow/flex-shrink will make the card take the full width of the flex container.

For each card
set flex-grow to 0
set flex-shrink to 0
make maximum-width empty