[nailer]

Flex is good when you need flexing. A single row grid, with variable width cells is simpler.

See elsewhere in the thread where I solved this and / or submit a fork your own version using flex.

[dimal]

Here's a fork.

https://codepen.io/mrdanimal/pen/VwGNOQw?editors=0100

As far as I could tell there was no visual change. It's not drastically different, but once you make everything flex, it's possible to remove a few of the grid properties.

[nailer]

(Off topic: can you please remove my name from your fork? Thanks)

[dimal]

Sure. I’m AFK but I’ll get it in a little while.