Frontend Design Skill

Source: mitsuhiko/agent-stuff (Apache-2.0)

Design and implement memorable frontend interfaces with a clear, intentional aesthetic. The output must be real, working code — not just mood boards. This skill is about design thinking + execution: every visual choice should be rooted in purpose and context.

When to Use

Use this skill when the user wants to:

• Create a new web page, landing page, dashboard, or app UI
• Design or redesign frontend components or screens
• Improve typography, layout, color, motion, or overall visual polish
• Convert a concept or brief into a high‑fidelity, coded interface

Inputs to Gather (or Assume)

Before coding, identify:

• Purpose & audience: What problem does this UI solve? Who uses it?
• Brand/voice: Any reference brands, tone, or visual inspiration?
• Technical constraints: Framework, library, CSS strategy, accessibility, performance
• Content constraints: Required copy, assets, data, features

If the user did not provide this, ask 2–4 targeted questions, or state reasonable assumptions in a short preface.

Design Thinking (Required)

Commit to a single, bold aesthetic direction. Name it and execute it consistently. Examples:

• Brutalist / raw / utilitarian
• Editorial / magazine / typographic
• Luxury / refined / minimal
• Retro‑futuristic / cyber / neon
• Art‑deco / geometric / ornamental
• Handcrafted / organic / textured

Avoid generic AI aesthetics. No “default” fonts, color schemes, or stock layouts.

Before writing code, define the system:

1. Visual direction — one sentence that describes the vibe
2. Differentiator — what should be memorable about this UI?
3. Typography system — display + body fonts, scale, weight, casing
4. Color system — dominant, accent, neutral; define as CSS variables
5. Layout strategy — grid rhythm, spacing scale, hierarchy plan
6. Motion strategy — 1–2 meaningful interaction moments

If the user wants code only, skip the explanation but still follow this internally.

Implementation Principles

• Working code: HTML/CSS/JS or framework code that runs as‑is
• Semantic & accessible: headings, labels, focus states, keyboard nav
• Responsive: fluid layouts, breakpoints, responsive typography
• Tokenized styling: CSS variables for colors, spacing, radii, shadows
• Modern layout: prefer CSS Grid/Flex, avoid brittle positioning hacks

Aesthetic Guidelines

Typography

• Typography should define the voice of the design
• Avoid default fonts (Inter, Roboto, Arial, system stacks)
• Use a distinct display font + a refined body font
• Implement a clear hierarchy (size, weight, spacing, casing)

Color & Theme

• Commit to a palette with a strong point‑of‑view
• Avoid timid, overused gradients (e.g., purple‑to‑pink on white)
• Use contrast intentionally and check legibility

Composition & Layout

• Encourage asymmetry, scale contrast, overlap, or grid breaks
• Use negative space deliberately (or controlled density if maximalist)
• Create visual rhythm and hierarchy through spacing and alignment

Detail & Atmosphere

• Add texture or depth when appropriate (noise, grain, subtle patterns)
• Use shadows/glows only when they serve the concept
• Consider unique borders, masks, or clip‑paths for distinct shapes

Motion & Interaction

• Use motion sparingly but meaningfully
• Favor one standout interaction over many tiny ones
• Honor prefers-reduced-motion

Avoid

• Cookie‑cutter hero + 3 card layouts
• Generic gradients and default font choices
• Unmotivated decorative elements
• Overly flat, characterless component libraries

Deliverables

• Provide full code with file names or component boundaries
• Make customization easy with CSS variables or config objects
• If assets are needed, provide inline SVGs or generative CSS patterns

Quality Checklist (Self‑validate)

• Aesthetic direction is unmistakable
• Typography feels intentional and expressive
• Layout and spacing are consistent and purposeful
• Color palette feels cohesive and legible
• Interactions enhance the experience without clutter
• Code runs as provided and is production‑ready

Remember: a design is only as strong as its commitment. Choose a direction and execute it relentlessly.