A bit grim, but it's been on my mind since I felt a bit of the quakes here

(v/vl
 {:width 800 :height 800
  :config {:projection {:type "mercator"}}
  :layer [{:data {:url ""
                  :format {:type "json" :property "features"}}
           :mark {:type "geoshape" :fill "white" :stroke "black"}}
          {:data {:url ""
                  :format {:type "json" :property "features"}}
           :mark {:type "geoshape" :fill "lightgray" :stroke "red"}
           :encoding {:color {}}}]})

@ben.sless that would be great with https://leva.mentat.org for the sliders

new mafs/clerk #C019ZQSPYG6 template in Mafs.cljs 0.2.0: https://github.com/mentat-collective/Mafs.cljs/tree/main/resources/mafs/clerk this generates a batteries-included Clerk project https://clerk-utils.mentat.org/#project-template, but tuned for Mafs.cljs, including an intro notebook with a few Mafs demos.