UI Design Brain
This skill provides a curated knowledge base of 60+ UI component patterns sourced from component.gallery and enriched with best practices, layout guidance, and usage rules. It replaces generic guessing with real design-system knowledge when generating interfaces.
Before writing any UI code, consult this skill to select the right components and follow their best practices. Read components.md for the full reference.
When to Use This Skill
Apply whenever the user asks to build, design, or generate:
- Web pages, landing pages, marketing sites
- SaaS dashboards, admin panels, settings pages
- Forms, data tables, navigation structures
- Modals, drawers, popovers, or overlay patterns
- Any React, HTML/CSS, or Tailwind UI component
Design Philosophy
Every generated interface should feel modern, minimal, and production-ready — not like a template.
Core Principles
- Restraint over decoration. Fewer elements, highly refined. White space is a feature.
- Typography carries hierarchy. Pair a distinctive display font with a clean body font. Maximize weight contrast between headings and labels.
- One strong color moment. Neutral palette first (warm off-whites, near-blacks, muted mid-tones). Introduce one confident accent. If it could appear on a poster or book cover, it's probably timeless.
- Spacing is structure. Use an 8 px grid. Tighter gaps group related elements; generous gaps let hero content breathe.
- Accessibility is non-negotiable. WCAG AA contrast minimums. Focus indicators. Semantic HTML. Keyboard navigation.
- No generic AI aesthetics. Avoid: purple-on-white gradients, Inter/Roboto defaults, evenly-spaced card grids, and cookie-cutter layouts. Every interface should feel designed for its specific context.
Quality Bar
The output should match what you'd expect from a senior product designer at a top SaaS company:
- Clean visual rhythm with intentional asymmetry
- Obvious interactive affordances (hover, focus, active states)
- Graceful edge cases (empty states, loading, error)
- Responsive without breakpoint artifacts
Workflow
Step 1 — Identify Components
Read the user's request and determine which UI components are needed. Reference components.md to find each component by name or alias.
Common mappings:
- "navigation" → Header, Navigation, Breadcrumbs, Tabs
- "form" → Form, Text input, Select, Checkbox, Radio button, Button
- "data display" → Table, Card, List, Badge, Avatar
- "feedback" → Alert, Toast, Modal, Spinner, Progress bar, Empty state
- "input" → Text input, Textarea, Select, Combobox, Datepicker, File upload, Slider
- "overlay" → Modal, Drawer, Popover, Tooltip, Dropdown menu
Step 2 — Apply Best Practices
For each component in the interface, follow its best practices from the reference. Key rules that apply broadly:
Layout
- Single-column forms — faster to scan
- Consistent vertical lanes in repeated rows (lists, tables)
- Fixed-width slots for icons and actions, even when empty
- Cards: media → title → meta → action hierarchy
Interaction
- Buttons: verb-first labels ("Save changes", not "Submit"), one primary per section
- Modals: always provide X, Cancel, and Escape; trap focus; return focus on close
- Toasts: auto-dismiss 4–6 s, allow manual dismiss, stack newest on top
- Toggles: immediate effect only — use checkboxes in forms that require Save
Typography & Spacing
- Strict heading hierarchy (h1 → h2 → h3), one h1 per page
- Minimum 44 px touch targets on mobile
- Labels above inputs (vertical forms) or beside (horizontal)
- Placeholder text as format hint, never as label replacement
States
- Empty states: illustration + helpful headline + primary CTA
- Loading: skeleton screens > spinners (show after 300 ms delay)
- Validation: inline on blur, not on every keystroke
- Disabled elements: visually distinct but still readable
Step 3 — Choose a Design Direction
Select the style preset that best matches the user's intent, or ask if unclear:
Modern SaaS (default)
- Neutral palette, one strong accent
- 8 px grid, generous white space
- Clean, professional, spacious
Apple-level Minimal
- Near-monochrome, warm grays
- Large type hierarchy, tight tracking on display text
- Abundant white space, micro-interactions (150–250 ms ease-out)
Enterprise / Corporate
- Information-dense, well-defined regions
- Compact spacing scale (4/8/12/16/24 px)
- Robust form handling, fully keyboard-navigable
Creative / Portfolio
- Bold, expressive, strong visual personality
- Asymmetric layouts, dramatic scale contrast
- Editorial typography, vivid accent colors
Data Dashboard
- Data-dense, optimised for scannability
- Consistent vertical alignment across rows
- Clear metric hierarchy: KPI → trend → detail
Step 4 — Generate Code
Write production-ready code following these rules:
Stack: React + Tailwind CSS (unless user specifies otherwise)
Spacing: Tailwind spacing scale (p-2, gap-4, etc.) on an 8px grid
Colors: CSS variables or Tailwind config for palette consistency
Typography: Tailwind text utilities; expressive font pairings via Google Fonts
States: Implement hover, focus, active, disabled for all interactive elements
Responsive: Mobile-first; test at 375, 768, 1440 px
Accessibility: Semantic HTML, ARIA where needed, focus managementComponent Quick Reference
Below are the 15 most commonly needed components. For the full 60+ component reference with best practices, aliases, and layout examples, see components.md.
| Component | When to use | Key rule |
|---|---|---|
| Button | Trigger actions | Verb-first labels; one primary per section |
| Card | Represent an entity | Media → title → meta → action; shadow OR border, not both |
| Modal | Focused attention | Trap focus; X + Cancel + Escape to close |
| Navigation | Page/section links | 5–7 items max; clear active state |
| Table | Structured data | Sticky header; right-align numbers; sortable columns |
| Tabs | Switch panels | 2–7 tabs; active indicator; accordion on mobile |
| Form | Collect input | Single column; labels above; inline validation on blur |
| Toast | Brief confirmation | Auto-dismiss 4–6 s; undo action for destructive ops |
| Alert | Important status | Semantic colors + icon; max 2 sentences |
| Drawer | Secondary panel | Right for detail, left for nav; 320–480 px desktop |
| Search input | Find content | Cmd/Ctrl+K shortcut; debounce 200–300 ms |
| Empty state | No data | Illustration + headline + CTA; positive framing |
| Skeleton | Loading placeholder | Match actual layout shape; shimmer animation |
| Badge | Status/metadata label | 1–2 words; pill shape for status; limited color palette |
| Dropdown menu | Action/nav options | 7±2 items; destructive actions last in red |
Anti-Patterns to Avoid
Never generate these — they signal generic, low-quality UI:
- Rainbow badges — every status a different bright color with no semantic meaning
- Modal inside modal — use a page or drawer for complex flows
- Disabled submit with no explanation — always indicate what's missing
- Spinner for predictable layouts — use skeleton screens instead
- "Click here" links — link text must describe the destination
- Hamburger menu on desktop — use visible navigation when space allows
- Auto-advancing carousels — let users control navigation
- Placeholder-only form fields — always use visible labels
- Equal-weight buttons — establish primary/secondary/tertiary hierarchy
- Tiny text (< 12 px) — body text minimum 14 px, prefer 16 px