node color: deductive strength (weakest E → strongest)
→ arrow L → L′ means L′ ⊊ L (proved in Lean)
+n L+n merges n further logics equal to L (hover to list them)
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Could not load zoo.json.

This page must be served over HTTP next to the JSON file. From the repository root run just zoo-serve (after just zoo if the JSON has not been generated yet) and open the printed URL.