This article has no byline and is on a website that is even more weirdly specific than this one is, but I appreciate the trick here. A seven-column grid makes for a calendar layout pretty quick. You can let the days (grid items) fall onto it naturally, except kick the first day over to the correct first column with grid-column-start.
I’d go with an <ol> rather than a <ul> just because it seems like days are definitely ordered.
The days as-a-list don’t really bother me since maybe that makes semantic sense to the content of the calendar (assuming it has some)
But… seeing the titles of the days-of-the-week as the first items in the same list feels weird. Almost like that should be a separate list or something.
Or maybe it should all just be a <table> since it’s sort of tabular data (it stands to reason you might want to cross-reference and look at all Thursdays or whatever).
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