UI Design System

# UI Design System

Generate design tokens, create color palettes, calculate typography scales, build component systems, and prepare developer handoff documentation.

---

## Table of Contents

- [Trigger Terms](#trigger-terms)
- [Workflows](#workflows)
  - [Workflow 1: Generate Design Tokens](#workflow-1-generate-design-tokens)
  - [Workflow 2: Create Component System](#workflow-2-create-component-system)
  - [Workflow 3: Responsive Design](#workflow-3-responsive-design)
  - [Workflow 4: Developer Handoff](#workflow-4-developer-handoff)
- [Tool Reference](#tool-reference)
- [Quick Reference Tables](#quick-reference-tables)
- [Knowledge Base](#knowledge-base)

---

## Trigger Terms

Use this skill when you need to:

- "generate design tokens"
- "create color palette"
- "build typography scale"
- "calculate spacing system"
- "create design system"
- "generate CSS variables"
- "export SCSS tokens"
- "set up component architecture"
- "document component library"
- "calculate responsive breakpoints"
- "prepare developer handoff"
- "convert brand color to palette"
- "check WCAG contrast"
- "build 8pt grid system"

---

## Workflows

### Workflow 1: Generate Design Tokens

**Situation:** You have a brand color and need a complete design token system.

**Steps:**

1. **Identify brand color and style**
   - Brand primary color (hex format)
   - Style preference: `modern` | `classic` | `playful`

2. **Generate tokens using script**
   ```bash
   python scripts/design_token_generator.py "#0066CC" modern json
   ```

3. **Review generated categories**
   - Colors: primary, secondary, neutral, semantic, surface
   - Typography: fontFamily, fontSize, fontWeight, lineHeight
   - Spacing: 8pt grid-based scale (0-64)
   - Borders: radius, width
   - Shadows: none through 2xl
   - Animation: duration, easing
   - Breakpoints: xs through 2xl

4. **Export in target format**
   ```bash
   # CSS custom properties
   python scripts/design_token_generator.py "#0066CC" modern css > design-tokens.css

   # SCSS variables
   python scripts/design_token_generator.py "#0066CC" modern scss > _design-tokens.scss

   # JSON for Figma/tooling
   python scripts/design_token_generator.py "#0066CC" modern json > design-tokens.json
   ```

5. **Validate accessibility**
   - Check color contrast meets WCAG AA (4.5:1 normal, 3:1 large text)
   - Verify semantic colors have contrast colors defined

---

### Workflow 2: Create Component System

**Situation:** You need to structure a component library using design tokens.

**Steps:**

1. **Define component hierarchy**
   - Atoms: Button, Input, Icon, Label, Badge
   - Molecules: FormField, SearchBar, Card, ListItem
   - Organisms: Header, Footer, DataTable, Modal
   - Templates: DashboardLayout, AuthLayout

2. **Map tokens to components**

   | Component | Tokens Used |
   |-----------|-------------|
   | Button | colors, sizing, borders, shadows, typography |
   | Input | colors, sizing, borders, spacing |
   | Card | colors, borders, shadows, spacing |
   | Modal | colors, shadows, spacing, z-index, animation |

3. **Define variant patterns**

   Size variants:
   ```
   sm: height 32px, paddingX 12px, fontSize 14px
   md: height 40px, paddingX 16px, fontSize 16px
   lg: height 48px, paddingX 20px, fontSize 18px
   ```

   Color variants:
   ```
   primary: background primary-500, text white
   secondary: background neutral-100, text neutral-900
   ghost: background transparent, text neutral-700
   ```

4. **Document component API**
   - Props interface with types
   - Variant options
   - State handling (hover, active, focus, disabled)
   - Accessibility requirements

5. **Reference:** See `references/component-architecture.md`

---

### Workflow 3: Responsive Design

**Situation:** You need breakpoints, fluid typography, or responsive spacing.

**Steps:**

1. **Define breakpoints**

   | Name | Width | Target |
   |------|-------|--------|
   | xs | 0 | Small phones |
   | sm | 480px | Large phones |
   | md | 640px | Tablets |
   | lg | 768px | Small laptops |
   | xl | 1024px | Desktops |
   | 2xl | 1280px | Large screens |

2. **Calculate fluid typography**

   Formula: `clamp(min, preferred, max)`

   ```css
   /* 16px to 24px between 320px and 1200px viewport */
   font-size: clamp(1rem, 0.5rem + 2vw, 1.5rem);
   ```

   Pre-calculated scales:
   ```css
   --fluid-h1: clamp(2rem, 1rem + 3.6vw, 4rem);
   --fluid-h2: clamp(1.75rem, 1rem + 2.3vw, 3rem);
   --fluid-h3: clamp(1.5rem, 1rem + 1.4vw, 2.25rem);
   --fluid-body: clamp(1rem, 0.95rem + 0.2vw, 1.125rem);
   ```

3. **Set up responsive spacing**

   | Token | Mobile | Tablet | Desktop |
   |-------|--------|--------|---------|
   | --space-md | 12px | 16px | 16px |
   | --space-lg | 16px | 24px | 32px |
   | --space-xl | 24px | 32px | 48px |
   | --space-section | 48px | 80px | 120px |

4. **Reference:** See `references/responsive-calculations.md`

---

### Workflow 4: Developer Handoff

**Situation:** You need to hand off design tokens to development team.

**Steps:**

1. **Export tokens in required formats**
   ```bash
   # For CSS projects
   python scripts/design_token_generator.py "#0066CC" modern css

   # For SCSS projects
   python scripts/design_token_generator.py "#0066CC" modern scss

   # For JavaScript/TypeScript
   python scripts/design_token_generator.py "#0066CC" modern json
   ```

2. **Prepare framework integration**

   **React + CSS Variables:**
   ```tsx
   import './design-tokens.css';

   <button className="btn btn-primary">Click</button>
   ```

   **Tailwind Config:**
   ```javascript
   const tokens = require('./design-tokens.json');

   module.exports = {
     theme: {
       colors: tokens.colors,
       fontFamily: tokens.typography.fontFamily
     }
   };
   ```

   **styled-components:**
   ```typescript
   import tokens from './design-tokens.json';

   const Button = styled.button`
     background: ${tokens.colors.primary['500']};
     padding: ${tokens.spacing['2']} ${tokens.spacing['4']};
   `;
   ```

3. **Sync with Figma**
   - Install Tokens Studio plugin
   - Import design-tokens.json
   - Tokens sync automatically with Figma styles

4. **Handoff checklist**
   - [ ] Token files added to project
   - [ ] Build pipeline configured
   - [ ] Theme/CSS variables imported
   - [ ] Component library aligned
   - [ ] Documentation generated

5. **Reference:** See `references/developer-handoff.md`

---

## Tool Reference

### design_token_generator.py

Generates complete design token system from brand color.

| Argument | Values | Default | Description |
|----------|--------|---------|-------------|
| brand_color | Hex color | #0066CC | Primary brand color |
| style | modern, classic, playful | modern | Design style preset |
| format | json, css, scss, summary | json | Output format |

**Examples:**

```bash
# Generate JSON tokens (default)
python scripts/design_token_generator.py "#0066CC"

# Classic style with CSS output
python scripts/design_token_generator.py "#8B4513" classic css

# Playful style summary view
python scripts/design_token_generator.py "#FF6B6B" playful summary
```

**Output Categories:**

| Category | Description | Key Values |
|----------|-------------|------------|
| colors | Color palettes | primary, secondary, neutral, semantic, surface |
| typography | Font system | fontFamily, fontSize, fontWeight, lineHeight |
| spacing | 8pt grid | 0-64 scale, semantic (xs-3xl) |
| sizing | Component sizes | container, button, input, icon |
| borders | Border values | radius (per style), width |
| shadows | Shadow styles | none through 2xl, inner |
| animation | Motion tokens | duration, easing, keyframes |
| breakpoints | Responsive | xs, sm, md, lg, xl, 2xl |
| z-index | Layer system | base through notification |

---

## Quick Reference Tables

### Color Scale Generation

| Step | Brightness | Saturation | Use Case |
|------|------------|------------|----------|
| 50 | 95% fixed | 30% | Subtle backgrounds |
| 100 | 95% fixed | 38% | Light backgrounds |
| 200 | 95% fixed | 46% | Hover states |
| 300 | 95% fixed | 54% | Borders |
| 400 | 95% fixed | 62% | Disabled states |
| 500 | Original | 70% | Base/default color |
| 600 | Original × 0.8 | 78% | Hover (dark) |
| 700 | Original × 0.6 | 86% | Active states |
| 800 | Original × 0.4 | 94% | Text |
| 900 | Original × 0.2 | 100% | Headings |

### Typography Scale (1.25x Ratio)

| Size | Value | Calculation |
|------|-------|-------------|
| xs | 10px | 16 ÷ 1.25² |
| sm | 13px | 16 ÷ 1.25¹ |
| base | 16px | Base |
| lg | 20px | 16 × 1.25¹ |
| xl | 25px | 16 × 1.25² |
| 2xl | 31px | 16 × 1.25³ |
| 3xl | 39px | 16 × 1.25⁴ |
| 4xl | 49px | 16 × 1.25⁵ |
| 5xl | 61px | 16 × 1.25⁶ |

### WCAG Contrast Requirements

| Level | Normal Text | Large Text |
|-------|-------------|------------|
| AA | 4.5:1 | 3:1 |
| AAA | 7:1 | 4.5:1 |

Large text: ≥18pt regular or ≥14pt bold

### Style Presets

| Aspect | Modern | Classic | Playful |
|--------|--------|---------|---------|
| Font Sans | Inter | Helvetica | Poppins |
| Font Mono | Fira Code | Courier | Source Code Pro |
| Radius Default | 8px | 4px | 16px |
| Shadows | Layered, subtle | Single layer | Soft, pronounced |

---

## Knowledge Base

Detailed reference guides in `references/`:

| File | Content |
|------|---------|
| `token-generation.md` | Color algorithms, HSV space, WCAG contrast, type scales |
| `component-architecture.md` | Atomic design, naming conventions, props patterns |
| `responsive-calculations.md` | Breakpoints, fluid typography, grid systems |
| `developer-handoff.md` | Export formats, framework setup, Figma sync |

---

## Validation Checklist

### Token Generation
- [ ] Brand color provided in hex format
- [ ] Style matches project requirements
- [ ] All token categories generated
- [ ] Semantic colors include contrast values

### Component System
- [ ] All sizes implemented (sm, md, lg)
- [ ] All variants implemented (primary, secondary, ghost)
- [ ] All states working (hover, active, focus, disabled)
- [ ] Uses only design tokens (no hardcoded values)

### Accessibility
- [ ] Color contrast meets WCAG AA
- [ ] Focus indicators visible
- [ ] Touch targets ≥ 44×44px
- [ ] Semantic HTML elements used

### Developer Handoff
- [ ] Tokens exported in required format
- [ ] Framework integration documented
- [ ] Design tool synced
- [ ] Component documentation complete