Server: one THEMES list; `theme` is read from the data directory's proddash.json like port/adminPasscode; GET /api/theme is public (dashboards need it before anyone logs in) and returns { theme, themes: [{ id, name, colors: { bg, panel, accent } }] }; POST /api/admin/theme { theme } validates against the list, writes the key into proddash.json keeping every other key, updates the in-memory value and broadcasts a `theme` shell event over /api/events.
style.css: four html[data-theme] variable sets appended at the end — Harbor (navy/cyan), Graphite (charcoal/blue), Ember (warm black/orange) and Daylight (light, for daytime FOH) — each swapping exactly the eight palette variables; :root stays Booth, the default.
shell.js: a self-contained theme section — the last-known theme (localStorage proddash:theme) goes on synchronously, then the server's answer, then live changes via the SSE event; one listener line added in subscribeEvents. Tile-configured colours are set on the tile and still win.
README: a Themes subsection under Configure and the `theme` row in the proddash.json key table.
Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>
