For this experiment, I took a stab at defining the grid with grid-template-areas, which turned out to be an very helpful way to organize the menu items and better visualize how things would move around.
Jules Forrest, Grids revisited

Jules Forrest a converti des mises en page complexes à base de colonnes (journaux, affiches, menus) avec CSS grid. Impressionnant !

Via je ne sais plus qui.