a17: colored space, derived composition, subtraction, incumbent-as-evidence

Four lines from the r10 dual consultation (codex gpt-5.6-sol + gemini
3.5-pro on the actual HTMLs) and the hero-probe micro-eval: the probe
isolated a first-viewport monoculture (same split template in every
sample, control and skill alike) and showed these lines break it while
codex's raw 15-liner alone does not. The incumbent sentence swap fixes
the r10 root cause both consultants independently identified.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

skill/SKILL.src.md

@@ -24,7 +24,7 @@ Approach every design task as the design lead at a small studio known for giving
 
 **Existing worlds are sacred.** Most of impeccable's work happens inside a site or app that already exists. When the surface has a committed design system (real tokens, deliberately chosen faces, a palette the brand owns), work inside that world: extend it, sharpen it, leave it unmistakably the same brand, and never degrade a working page's performance. Inventing parallel colors, fonts, or styles on an existing surface is a defect, not creativity. A scoped refinement keeps the named scope's content and media footprint unless the brief explicitly changes them; build the added emphasis by recomposing what is already there through hierarchy, proportion, rhythm, and the system's own motifs. <!-- rule:skill-existing-world-preservation -->
 
-**New identity work reads the playbook first.** When nothing committed exists (greenfield, or a codebase with no real tokens or chosen faces), or the user asks for a redesign that discards the current look, you MUST read [reference/new-work.md](reference/new-work.md) before making any design decision. Not optional, not skippable under time pressure: producing new identity without it yields the generic default this skill exists to prevent. A redesign is new work; derive the concept from the subject and the brief, not from the incumbent page's structure or styling. `context.mjs` prints this directive when it detects the situation. Scoped fixes inside an existing world don't need the playbook; the craft floor below governs them. <!-- rule:skill-new-work-gate -->
+**New identity work reads the playbook first.** When nothing committed exists (greenfield, or a codebase with no real tokens or chosen faces), or the user asks for a redesign that discards the current look, you MUST read [reference/new-work.md](reference/new-work.md) before making any design decision. Not optional, not skippable under time pressure: producing new identity without it yields the generic default this skill exists to prevent. A redesign is new work; read the incumbent as evidence, not as a template or an obstacle: where it carries a deliberate, ownable visual idea, preserve that lineage and intensify it instead of replacing it with contemporary polish. `context.mjs` prints this directive when it detects the situation. Scoped fixes inside an existing world don't need the playbook; the craft floor below governs them. <!-- rule:skill-new-work-gate -->
 
 ## Craft floor
 

skill/reference/new-work.md

@@ -4,7 +4,7 @@ You are reading this because nothing committed exists yet (greenfield), or the u
 
 ## Seed
 
-If the project is brand-new (no committed tokens, fonts, or brand colors found in the code), run `node {{scripts_path}}/palette.mjs` for a brand seed color. The seed exists to break your reflex palette; it does not override the subject. When the subject's world clearly dictates color (an era, a place, a material, a medium), derive the palette from that world and use the seed only to check yourself. Otherwise anchor on it. The palette has exactly two legitimate sources: the seed, or the subject's world. What the category usually looks like is neither, and quietly swapping in the category's habitual palette and theme after drawing a seed is the reflex this step exists to break. Use OKLCH throughout. Skip this entirely when the code already has committed brand colors: identity-preservation wins.
+If the project is brand-new (no committed tokens, fonts, or brand colors found in the code), run `node {{scripts_path}}/palette.mjs` for a brand seed color. The seed exists to break your reflex palette; it does not override the subject. When the subject's world clearly dictates color (an era, a place, a material, a medium), derive the palette from that world and use the seed only to check yourself. Otherwise anchor on it. The palette has exactly two legitimate sources: the seed, or the subject's world. What the category usually looks like is neither, and quietly swapping in the category's habitual palette and theme after drawing a seed is the reflex this step exists to break. Color commits at page scale: fields that own whole regions, not accents scattered over a neutral ground. A dark page with one glowing accent is the category's reflex, not a choice. Use OKLCH throughout. Skip this entirely when the code already has committed brand colors: identity-preservation wins.
 
 ## Ground it in the subject
 
@@ -20,11 +20,11 @@ Then state the chosen direction as a contract, written as a comment block at the
 
 Plan a compact token system in your reasoning: palette, type, layout concept in one sentence, and a **signature**: the one element this surface will be remembered by, drawn from the subject's world. A signature carries weight: sized and placed so the page organizes itself around it. The layout has exactly two legitimate sources: the concept, or the content's own structure. The category's habitual skeleton is neither, and assembling the usual sections in the usual order after choosing a concept is the same reflex the palette rule breaks, expressed in structure. <!-- rule:skill-layout-source-exclusivity --> Then audit the plan: work through what you'd produce for a similar brief from another client, and wherever the two plans converge (same palette family, same face, same skeleton), that part is your generic default, not a choice. Revise it, then build, deriving every color and type decision from the revised plan.
 
-**The first viewport is a thesis, not a header.** The visitor should meet the concept doing its job immediately: the work itself, the product working, the content answering, the task at hand. Generic chrome around a generic promise is the template answer; earn it or replace it. The memory test: if someone left after one viewport, what would they describe an hour later? If the honest answer is a mood ("clean", "tasteful"), the concept hasn't committed yet.
+**The first viewport is a thesis, not a header.** The visitor should meet the concept doing its job immediately: the work itself, the product working, the content answering, the task at hand. Generic chrome around a generic promise is the template answer; earn it or replace it. The composition is derived the same way the palette is: if a neighboring product could ship the same arrangement of the same blocks, the viewport isn't composed yet. The memory test: if someone left after one viewport, what would they describe an hour later? If the honest answer is a mood ("clean", "tasteful"), the concept hasn't committed yet.
 
 **Everything bold, nothing bland.** Bold is not decoration and not clutter; it is commitment to the concept, carried through every section. Commitment takes whatever form the concept and the mode demand: maximal or severely clean, drenched in color or nearly monochrome, copy so precise it stings, the product demonstrating itself, or a system so exact it feels inevitable (a decisive typographic voice, one owned accent, an unmistakable rhythm). A spare page built on one uncompromising idea is bold; a busy page of tasteful defaults is bland. The signature is where the concept peaks, not the only place it lives; cut anything that neither advances the concept nor serves the visitor's mode. Polish is the floor, not the point: when torn between refined and committed, commit.
 
-**Prove, don't claim.** A surface earns belief by showing its subject doing its job: the interface at work, the mechanism dramatized, the content delivering, specifics a competitor couldn't copy-paste. The visitor should understand by looking, before reading a word. Sections that restate a claim in different words add length, not substance.
+**Prove, don't claim.** A surface earns belief by showing its subject doing its job: the interface at work, the mechanism dramatized, the content delivering, specifics a competitor couldn't copy-paste. The visitor should understand by looking, before reading a word. Sections that restate a claim in different words add length, not substance, and a page that demonstrates everything you discovered while planning reads as cruft: build only the sections a visitor needs to understand, trust, and act.
 
 ## Commit