Site · Logo: the letter E in iso blocks, in the header, the favicon, the touch icon and the OG image

One geometry in src/iso/mark.ts, drawn by the engine the miniatures use. The favicon follows the system's mode; scripts/favicon.mjs takes its colors from styles.css. Below 768px the header shows the mark alone, its word kept as the link's name.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

TASKS.md

@@ -186,6 +186,7 @@ Per-component lines live in `tasks/`. Tags there:
 - [x] T50f Rendering · Docs: a guide with an example `scripts/check.sh` compiles; AGENTS.md
 - [x] T50g Rendering · Acceptance: the checklist, item by item
 - [x] T51 Showcase · an apps page fed by a public repo — `tasks/showcase.md`
+- [x] T52 Logo · an isometric mark for the header, favicon and OG image — `tasks/logo.md`
 
 ## T00 detail