It doesn't fit my definition of "clean" at all, but that's a subjective word anyway. I do have some feedback (unrelated to being clean):

- The search field is arguably the most important element on the site. It might benefit from a magnifying glass icon and/or some visual distinctions that make it actually look like a text input for searching. It's thick border and shadow make it look like all the other boxes on the page that have thick borders and shadows!

- Speaking of the search field, it would be really nice if it supported fuzzy search. For example, I searched for "greater than" and got no results. I had to search for "greater-than" (with a dash) to find the math symbols (like ≥).

- The small font size of the symbols makes them really hard to see for old people like me who are pretending not to be old.

- Ditch the analytics and cookie consent nonsense. These are anti-developer!