This is a Mapbox GL JS based style for Geolonia.
https://github.com/maputnik/editor/wiki/Maputnik-CLI
$ curl -L https://github.com/maputnik/editor/releases/download/v1.6.1/maputnik_darwin -o /usr/local/bin/maputnik
$ chmod 755 /usr/local/bin/maputnik
maputnik --watch --file ./style.json
Then access the Maputnik editor GUI at localhost:8000.