A reference doc (docs/nps-resources.adoc) covering everything looked at while pulling icons/controls/theme colors from NPS's mapping ecosystem: what's actually in use (symbol-library, home-button, the Park Tiles-inspired offline palette), what was considered and deliberately skipped (svg-icons, markdown-handlebars, the unmerged overview/carto/wms branches) and why, the Park Tiles cartography research (Harpers Ferry Center lineage, the four style variants, why the actual tile service is off-limits via Mapbox Atlas licensing, the public style JSON and Mapbox Studio style IDs found), and the still-open upstream PR revising artwork for three icons we use. Worth having as a knowledge base rather than re-deriving any of this from scratch next time — NPS's tooling has repeatedly turned out to be a better source than building something from nothing.