Responsive Design using CSS Flexbox and Grid

What challenges did you encounter, and how did you overcome them?

The biggest challenge for me was moving from the mobile layout to the desktop layout. I started out with the mobile view, which was pretty easy. The desktop view, however, was more challenging. The difficult part was that I did not want to modify the mobile layout too much. My solution for this was to simply change my display from flexbox to grid using a media query. That seems to have worked pretty well, but then my next challenge was actually using grid. I am more used to flexbox, and grid is still quite a bit difficult for me to grasp right now. I did some research and watched some videos about it and seemed to have found a solution that works, but I still feel like I need to learn more to understand it better.