docs(web): add design context for marketplace web app (#128)

Add .impeccable.md with full design context and reference it from
CLAUDE.md. Defines five key design principles for apps/web/: content
clarity, polish, efficient discovery, inclusivity, and design system
loyalty.

Author: amondnet

.impeccable.md

@@ -0,0 +1,26 @@
+## Design Context
+
+### Users
+Developers and engineering teams who use Claude Code and want to extend it with plugins. They arrive with a specific intent: discover, evaluate, and install plugins quickly. Both individual developers seeking productivity tools and teams evaluating plugins for adoption. The interface should evoke **confidence, efficiency, and trust** -- users are installing code that runs in their development environment, so credibility signals matter.
+
+### Brand Personality
+**Polished, modern, trustworthy.**
+
+Voice is technical but approachable. Tone is confident without being corporate. The marketplace should feel like a curated, well-maintained ecosystem rather than a dumping ground. Passion Factory maintains this as a community resource, so it should communicate care and quality.
+
+### Aesthetic Direction
+- **Visual tone:** Clean and refined, similar to Vercel, Linear, or Nuxt Modules. Premium developer tool aesthetic with generous whitespace, clear hierarchy, and purposeful use of color.
+- **References:** Vercel Marketplace (sleek cards, trust signals), Nuxt Modules (clean grid, developer-friendly), Linear (refined spacing, dark mode excellence)
+- **Anti-references:** WordPress plugin directory (cluttered, ad-heavy), generic SaaS landing pages (stock photos, marketing fluff), overly playful/childish aesthetics
+- **Theme:** Light and dark mode (already supported via Nuxt UI). Dark mode should feel first-class, not an afterthought.
+- **Colors:** Nuxt UI defaults with primary color. Badge colors (amber, orange, purple, blue) for author/feature differentiation. No custom brand palette needed -- lean into the design system.
+- **Typography:** System font stack with Korean support (already configured). Prioritize readability and clear hierarchy over decorative typography.
+- **Icons:** Heroicons (UI) + Simple Icons (brand logos). Consistent sizing and alignment.
+
+### Design Principles
+
+1. **Content-first clarity** -- Plugin name, description, and install action should be instantly scannable. Every visual element must earn its place.
+2. **Trust through polish** -- Consistent spacing, aligned elements, and refined details signal that this marketplace (and its plugins) are well-maintained.
+3. **Efficient discovery** -- Users should find what they need in seconds. Search, filter, and card layout should minimize cognitive load.
+4. **Inclusive by default** -- WCAG AA compliance, respects reduced motion preferences, works well in both light and dark modes, supports Korean and English text.
+5. **Design system loyalty** -- Use Nuxt UI components and Tailwind utilities as intended. Avoid custom CSS overrides unless the design system genuinely can't express the intent. Consistency > novelty.

CLAUDE.md

@@ -481,4 +481,14 @@ Run this before committing new plugins or after modifying `plugin.json`.
 - This repository serves as both a plugin marketplace and a collection of plugin implementations
 - Each plugin can be independently versioned and released
 - MCP servers provide the runtime interface between Claude Code and plugin functionality
-- Plugins are designed to be easily toggled on/off by users
+- Plugins are designed to be easily toggled on/off by users
+
+## Design Context
+
+See `.impeccable.md` for full design context. Key principles for the marketplace web app (`apps/web/`):
+
+1. **Content-first clarity** -- Plugin name, description, and install action should be instantly scannable.
+2. **Trust through polish** -- Consistent spacing, aligned elements, and refined details.
+3. **Efficient discovery** -- Users should find what they need in seconds.
+4. **Inclusive by default** -- WCAG AA, reduced motion, light/dark mode, Korean + English.
+5. **Design system loyalty** -- Use Nuxt UI components and Tailwind as intended. Consistency > novelty.