/css/ - CSS Masters

Hey everyone, I've been struggling with this flexbox alignment issue for a while now and could really use some help! im trying to center align some elements both horizontally and vertically within a container using flexbox, but no matter what combinations of justify-content, align-items, and align-self properties I try, I cant seem to get it right. Any suggestions or best practices would be greatly appreciated! Thank you in advance for your time and expertise!