codex-design-system

TL;DR

Load before any UI/frontend task. This skill brings 30 palettes, 21 free font pairings, 20 layout patterns, 15 micro-interactions, composition rules, current trends, and developer-UI anti-pattern fixes. Anti-generic rules: no default blue, no plain white card stacks, no bootstrap look.

Activation

1. Activate when task involves UI, frontend, styling, component work, or landing-page creation.
2. Activate on $design or "make it look premium/modern/creative".
3. Auto-load when frontend-specialist agent is active.
4. Pair with codex-design-md when the project needs a durable DESIGN.md contract or token export.

Anti-Generic Rules (HARD)

• NEVER use default blue (#007bff, #2196F3, #3B82F6) or default purple (#6C63FF, #7C3AED) unless the chosen palette in references/palettes.md explicitly uses it.
• NEVER ship plain white cards with border-radius: 8px and box-shadow: 0 2px 4px rgba(0,0,0,0.1).
• NEVER use system fonts or unnamed "sans-serif"; specify exact font families and fallbacks.
• NEVER build a fully symmetrical layout without hierarchy through size, spacing, color, or motion.
• ALWAYS choose a palette from references/palettes.md before writing UI code.
• ALWAYS choose a font pair from references/typography.md.
• ALWAYS apply at least one composition principle from references/composition.md.
• ALWAYS add at least two micro-interactions from references/micro-interactions.md.

Design Decision Flow

1. Decide the mood: premium, bold, calm, editorial, playful, technical, or luxury.
2. Pick one palette from references/palettes.md.
3. Pick one font pair from references/typography.md.
4. Pick one or two layout patterns from references/patterns.md.
5. Pick two or three micro-interactions from references/micro-interactions.md.
6. Check references/anti-patterns.md before finalizing.
7. Then write UI code with explicit values for color, type, spacing, radius, and shadow.

Reference Files

• references/palettes.md — 30 curated palettes with exact hex tokens, mood, app fit, and contrast ratios.
• references/typography.md — 21 free font pairings with imports, weights, style tags, and fallback stacks.
• references/patterns.md — 20 layout patterns with structure, responsive CSS, and usage boundaries.
• references/micro-interactions.md — 15 motion patterns with CSS or JS code.
• references/composition.md — Visual hierarchy, spacing, grids, storytelling flow, and emphasis rules.
• references/trends.md — Current design trends for 2025-2026 with code signatures and fit guidance.
• references/anti-patterns.md — 15 developer-UI mistakes with wrong/right code and violated principles.