lib-theme-acid: initial import (bold/identity-forward set, 2026-07)

One of four divergent candidates for the bold consumer theme family
(committed saturated color at 30-60% surface coverage, strong display
type). Includes the post-diverge fixes: heading color:inherit so brand
slabs keep their foreground pairing, plus per-theme refinements.

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

README.md

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+# lib-theme-acid
+
+**Chartreuse on black.** Festival/Wrapped energy for consumer surfaces that
+want an unmistakable identity — the committed color carries 30–60% of the
+surface, the opposite of a calm settings app.
+
+## Thesis
+
+Dark mode is the native identity: a near-black green-cast field
+(`oklch(0.16 0.01 130)`) with electric acid chartreuse
+(`oklch(0.87 0.21 128)`) carrying the type accents, the panels, and the
+fills. The signature pair is **black ink on acid** (~13:1) — the primary
+button, the user chat bubble, and the sidebar accents all run black-on-acid,
+never white-on-green. Cards step a clear ≥0.05 lighter than the field; the
+sidebar drops to a pure-black stripe so the acid accents hit hardest there.
+
+`:root` is the brand's **paper mode** — an honest light mode on a committed
+chartreuse-washed paper (`oklch(0.96 0.05 120)`, visibly acid, not cream)
+with near-black green ink. The primary inverts the signature: a deep
+green-black fill (`oklch(0.3 0.09 130)`) carrying acid-bright labels.
+
+Status never borrows the brand's lane: destructive is hot red (hue 25,
+light label); warning is amber 85, held clearly apart from the chartreuse in
+both hue and chroma; **success is pushed to teal (hue 175, dark ink)** so no
+second green ever fights the brand; info is cool blue 240. Charts are
+acid-led with a cool spectrum behind (128 / 240 / 330 / 190 / 40).
+
+Radius is a chunky-sharp `0.75rem`. Motion is punchy and fast
+(100/200/320/450ms) with **one real snappy spring**
+(`--ease-spring-snappy: cubic-bezier(0.2, 1.4, 0.3, 1)` — actual overshoot)
+reserved for affordances; gentle/bouncy alias to the standard ease.
+Selection is acid at 40% alpha. Elevation in dark mode is pure-black
+shadows; no glass (inert stubs).
+
+## Fonts
+
+Load in the **consuming app's** entry CSS, at the very top (never `@import`
+inside `theme.css` — it breaks PostCSS ordering):
+
+```css
+@import url("https://fonts.googleapis.com/css2?family=Archivo+Black&family=Space+Grotesk:wght@400;500;600;700&family=JetBrains+Mono:wght@400;500;600&display=swap");
+```
+
+- **Archivo Black** — headings. A single-weight display black: it only ships
+  weight 400, so the theme's heading rule pins `font-weight: 400` and lets
+  the blackness of the cut do the work. Tracking is tight (`-0.02em`).
+  Don't ask for bold — faux-bolding this face ruins it.
+- **Space Grotesk** (400/500/600/700) — body, labels, buttons. Consumer
+  register: body 1rem/1.55, label 0.875rem, caption 0.75rem, title
+  1.375rem, subtitle 1.125rem, headline 1.875rem, display 2.75rem,
+  hero 3.5rem.
+- **JetBrains Mono** (400/500/600) — code. Dark-mode syntax is a rave
+  terminal with discipline: acid keyword, cool companions (teal strings,
+  magenta numbers, blue functions, orange types).
+
+## Validation
+
+```bash
+node create-crema-app/scripts/validate-theme.mjs lib-theme-acid/theme.css
+# ✓ PASS — all mandatory tokens present, contrast floors met, no ban violations.
+```