Responsive 3 column preview component using flexbox

It did take me quite a bit of time to get the initial desktop implementation working but after that, the mobile view was rather easy. One problem that still persists is that as soon as the screen width hits the 50em max-width of the .wrapper class, the cards start shifting in size like this and I simply couldn't come up with a fix for this. I feel like the reusability of my solution is pretty bad so I'd appreciate some feedback a lot.

Thanks in advance :D