became an inline `<svg class="mark">`, one `<path>` per letter of b-e-n-c-h on a 1000-unit em (baseline y=740, x-height top y=210, ascender y=0), with the design's −0.015em tracking folded into the per-glyph translations.
-`fill:currentColor` gives the mark `--text` in both Night and Daylight from one copy, so it introduces no colour and in particular no state colour. `--logo-h:14px` (the wordmark's b-height, = 19px × 0.74) is the single token that sizes it.
-`.brand` gap 10px → 11px, per the design. This is the one place I moved a neighbour: the acceptance bullet says the path line sits where it did, but "What to build" asks for the design's spacing against that line, so I took the design. It is a 1px shift and the header's height is set by the view switcher, not the brand, so nothing reflows.
- The tab icon's dot became the wordmark's own `b` on the accent tile it already had (the design's app-icon treatment: accent ground, white letter). Both copies of the `b` are the same outline string, and a test keeps them equal.
- Still fully self-contained: no `@font-face`, no font file, no new request. A test pins the page's external URLs to exactly the three IBM Plex ones that were already there and would fail if a fourth appeared.
## To do before merging
1.**Look at the header in both themes.** Zilla Slab's own contours are not reachable from this environment — `curl` and Python are not permitted to a headless agent here, so I could not fetch or convert the font binary, and I have no browser to render into. The five outlines are therefore hand-authored in Zilla Slab's idiom (slab feet, 118-unit stems, 104-unit bars, top-left flags on `b`/`h`/`n`, vertically-sheared `c` and `e` terminals), not exported from the face. I verified each path is a closed, non-self-intersecting loop and that even-odd filling puts the counters in the right places by point-sampling every region, but that proves the letters are *well-formed*, not that they are *handsome*.
2.**If they are not right, swapping in real outlines is mechanical**: replace the five `d` attributes in the `<svg class="mark">` block and the one in the `<link rel="icon">`, keeping the `#mark-b` and favicon strings identical — `test_header_logo.TheTabIcon.test_it_is_the_wordmark_s_own_b` fails if they diverge, and the em grid is documented in the comment above the SVG.
## To know
- The design's `--logo` / `--logo-weight` / `--logo-track` custom properties are the control that swaps between the eight candidate faces; they have no meaning once the chosen face is outlined, so they are not carried over. `--logo-h` is what replaces them as the mark's one token.
- Task 22's tab retitling is already on `main` (`de5cedb`), so the icon change sits alongside a title that is already `<project> · bench`; nothing needed coordinating.
- Out of scope and left alone: the README's `# Bench`, and everything else in the design files (the docs-site directions in `Bench Docs.dc.html` are a whole separate body of work).
The engineering is production-quality and every mechanical invariant holds; the single open item is human visual verification, because the wordmark ships as **hand-authored approximations of Zilla Slab, not the design's real outlines**. The build is otherwise ready to merge.
**What is good (verified against the branch, not just the tests):**
- Scope is exactly the card: only `manager/core/board.html` (favicon + `.brand`) and the new `tests/test_header_logo.py`. No neighbouring header details "aligned" while in there.
- Self-contained (acceptance #2): no `@font-face`, no font file, no new request; the external-URL set is pinned to the three pre-existing IBM Plex ones.
- Theme mechanism correct: `fill:currentColor` → `--text` in both themes from one copy, no baked colour, none of the state tokens; `--logo-h` is the one sizing token.
- Favicon/wordmark `b` are byte-identical (I confirmed 2 occurrences of the same outline on-branch, `board.html:9` and `:495`), so they cannot drift; even-odd fill keeps the counters open.
- Neighbours preserved (acceptance #3): header padding/alignment, the mono path line, and the header control order are invariant-tested. CI green on 3.11 and 3.13.
**To do before merge (human — an agent re-run hits the same tooling wall):**
1. Eyeball the header in **Night and Daylight** against the design. The five glyphs are hand-drawn (design MCP needs interactive auth; the font binary was unreachable headless), so acceptance #1 ("matching the design") is unverified and cannot be closed from source. If the shapes are off, swapping in real outlines is mechanical — replace the five `d` strings in `<svg class="mark">` and the favicon's, keeping `#mark-b` and the icon identical (`test_header_logo.TheTabIcon` enforces it).
2. While there, confirm the mono path line still sits right: `.brand` gap moved 10px → 11px (disclosed, "per the design"), which acceptance #3 nominally forbids — trivial, but it's the one intentional neighbour shift.
**To know:**
- I requested changes purely to keep the card in your hands for that visual check; nothing in the code needs rework. Once the glyphs are confirmed against the design, this is an approve.
- I could not run the suite locally (sandbox denied `python3 -m unittest`), but both CI test jobs passed, which covers it.
