Design System

## 1. Visual Theme & Atmosphere

This is a warm editorial experience built on natural materials. Think: a well-curated
bookshop with soft overhead lighting and carefully chosen display shelves. The density
is low — generous whitespace signals confidence and clarity. Every element earns its
place; nothing decorative exists without functional purpose.

**Key attributes:** Warm, unhurried, editorial, confident
**Density:** Low — generous whitespace, single-column focus
**Personality:** Thoughtful librarian, not flashy storefront

## 2. Color Palette & Roles

### Primary
| Name | Hex | Role |
|------|-----|------|
| Terracotta Brand | #c96442 | Primary CTA, active states, brand anchors |
| Terracotta Hover | #b85838 | Hover/pressed state for primary actions |

### Neutral
| Name | Hex | Role |
|------|-----|------|
| Near Black | #141413 | Primary text, headings |
| Olive Gray | #5e5d59 | Secondary text, captions |
| Parchment | #f5f4ed | Page background, default canvas |
| Ivory White | #ffffff | Card surfaces, overlays |

### Semantic
| Name | Hex | Role |
|------|-----|------|
| Success Green | #2d7d46 | Confirmation, success states |
| Warning Amber | #c27217 | Warnings, attention needed |
| Error Red | #c24132 | Errors, destructive actions |
| Info Blue | #3b6fb5 | Informational states, links |

### Dark Mode (if applicable)
| Light Name | Dark Equivalent | Hex |
|------------|----------------|-----|
| Parchment | Deep Charcoal | #1a1a1a |
| Near Black | Off White | #e8e8e8 |

## 3. Typography Rules

### Font Stack
- **Display/Heading:** "Anthropic Serif", Georgia, "Times New Roman", serif
- **Body:** "Anthropic Sans", -apple-system, BlinkMacSystemFont, sans-serif
- **Code:** "Anthropic Mono", "SF Mono", "Fira Code", monospace

### Type Scale
| Level | Size | Weight | Line Height | Letter Spacing | Font |
|-------|------|--------|-------------|----------------|------|
| H1 | 48px / 3rem | 500 | 1.10 | -0.02em | Serif |
| H2 | 36px / 2.25rem | 500 | 1.15 | -0.01em | Serif |
| H3 | 24px / 1.5rem | 500 | 1.25 | 0 | Serif |
| H4 | 20px / 1.25rem | 600 | 1.30 | 0 | Sans |
| Body | 16px / 1rem | 400 | 1.60 | 0 | Sans |
| Small | 14px / 0.875rem | 400 | 1.50 | 0.01em | Sans |
| Caption | 12px / 0.75rem | 500 | 1.40 | 0.02em | Sans |

### Principles
- Headings use serif for warmth and authority
- Body text uses sans-serif for readability at small sizes
- Maximum line length: 65ch for body text
- Minimum font size: 14px (never go below)

## 4. Component Stylings

### Buttons
**Primary:**
- Background: Terracotta Brand (#c96442)
- Text: Ivory White (#ffffff), 16px Sans, weight 500
- Padding: 12px 24px
- Border radius: 8px
- Hover: Terracotta Hover (#b85838), translateY(-1px), shadow-sm
- Active: translateY(0), shadow-none
- Disabled: opacity 0.5, cursor not-allowed
- Transition: all 150ms ease-out

**Secondary:**
- Background: transparent
- Border: 1px solid Olive Gray (#5e5d59)
- Text: Near Black (#141413)
- Hover: background Parchment (#f5f4ed)

### Cards
- Background: Ivory White (#ffffff)
- Border: 1px solid rgba(0,0,0,0.06)
- Border radius: 12px
- Padding: 24px
- Shadow: 0 1px 3px rgba(0,0,0,0.04)
- Hover: shadow 0 4px 12px rgba(0,0,0,0.08), translateY(-2px)

### Inputs
- Border: 1px solid #d0d0d0
- Border radius: 8px
- Padding: 10px 14px
- Focus: border Terracotta Brand, ring 2px rgba(201,100,66,0.2)
- Error: border Error Red, ring 2px rgba(194,65,50,0.2)

### Navigation
...

## 5. Layout Principles

### Spacing Scale (base: 4px)
| Token | Value | Usage |
|-------|-------|-------|
| space-1 | 4px | Tight gaps, icon margins |
| space-2 | 8px | Related element spacing |
| space-3 | 12px | Component internal padding |
| space-4 | 16px | Standard gap between elements |
| space-6 | 24px | Section padding, card padding |
| space-8 | 32px | Between major sections |
| space-12 | 48px | Page-level vertical rhythm |
| space-16 | 64px | Hero/banner spacing |

### Grid
- Max content width: 1200px
- Column count: 12
- Gutter: 24px (space-6)
- Margin: 16px mobile, 24px tablet, auto desktop

### Border Radius Scale
| Token | Value | Usage |
|-------|-------|-------|
| radius-sm | 4px | Badges, tags |
| radius-md | 8px | Buttons, inputs |
| radius-lg | 12px | Cards, panels |
| radius-xl | 16px | Modals, dialogs |
| radius-full | 9999px | Avatars, pills |

## 6. Depth & Elevation

### Shadow Scale
| Level | Value | Usage |
|-------|-------|-------|
| shadow-none | none | Flat elements |
| shadow-sm | 0 1px 2px rgba(0,0,0,0.04) | Subtle lift (cards at rest) |
| shadow-md | 0 4px 12px rgba(0,0,0,0.08) | Hover states, active cards |
| shadow-lg | 0 8px 24px rgba(0,0,0,0.12) | Dropdowns, popovers |
| shadow-xl | 0 16px 48px rgba(0,0,0,0.16) | Modals, dialogs |

### Surface Hierarchy
1. **Base** — page background (Parchment)
2. **Raised** — cards, panels (Ivory White + shadow-sm)
3. **Floating** — dropdowns, tooltips (Ivory White + shadow-lg)
4. **Overlay** — modals, dialogs (Ivory White + shadow-xl + scrim)

## 7. Do's and Don'ts

### DO: Use semantic color names
```css
/* Good */
.button-primary { background: var(--color-terracotta-brand); }

/* Bad */
.button-primary { background: #c96442; }

/* Good — uses scale */
.card { padding: var(--space-6); margin-bottom: var(--space-8); }

/* Bad — 19px is not on the scale */
.card { padding: 19px; margin-bottom: 37px; }

### Section 8: Responsive Behavior

Breakpoints, mobile patterns, and adaptation rules.

```markdown
## 8. Responsive Behavior

### Breakpoints
| Name | Width | Target |
|------|-------|--------|
| mobile | < 640px | Phones |
| tablet | 640–1024px | Tablets, small laptops |
| desktop | > 1024px | Laptops, monitors |

### Touch Targets
- Minimum interactive element size: 44x44px
- Minimum spacing between targets: 8px

### Mobile Adaptations
- Navigation collapses to hamburger menu below 640px
- Cards stack single-column below 640px
- Font sizes: H1 reduces to 32px on mobile, H2 to 28px
- Side padding: 16px on mobile, 24px tablet, auto-center desktop

### Behavior Patterns
- Horizontal scrolling: never (use stacking or truncation)
- Images: responsive with srcset, max-width: 100%
- Tables: horizontal scroll wrapper below tablet breakpoint

## 9. Agent Prompt Guide

### Quick Reference
- Primary CTA color: Terracotta Brand (#c96442)
- Background: Parchment (#f5f4ed)
- Heading font: Serif, weight 500
- Body font: Sans, weight 400
- Standard spacing: 24px (space-6)
- Card radius: 12px (radius-lg)

### How to Use This Document
1. Before writing any UI code, read the full DESIGN.md
2. Reference specific section names when implementing: "Following Section 4: Buttons"
3. Use design token names in CSS (var(--color-terracotta-brand)), not raw hex values
4. Check Section 7 (Do's and Don'ts) before submitting
5. If a component is not covered, create it following existing patterns and flag for DESIGN.md update

### Example Component Prompt
"Create a hero section on Parchment (#f5f4ed) with a headline at H1 scale
(48px Serif weight 500, line-height 1.10). Use Near Black (#141413) text.
Add a subtitle in Olive Gray (#5e5d59) at Body scale (16px Sans, line-height 1.60).
Place a Terracotta Brand (#c96442) primary button with Ivory text, radius-md (8px)."

### Iteration Guide
- Change one component at a time
- Reference specific color names and token values
- Describe the component's state (default, hover, active, disabled)
- Specify responsive behavior for the component

--{category}-{name}[-{modifier}]

:root {
  --color-terracotta-brand: #c96442;
  --space-6: 24px;
  --radius-lg: 12px;
  --shadow-sm: 0 1px 2px rgba(0,0,0,0.04);
}

DESIGN.md → Cavekit acceptance criterion → Plan task → Implementation

- [ ] Component uses a card-like container [DESIGN.md: pattern not yet defined — flag for design update]

**Design Reference:** DESIGN.md Section {N} — {section name}