Design Tokens Structure

Overview

Establish the architectural foundation for a scalable design token system. Defines the three-layer token hierarchy (primitive → semantic → component) that enables theming, multi-brand support, and maintainable design systems.

When to Use

• Starting a new design system from scratch
• Restructuring an existing token system
• Adding multi-theme or multi-brand support
• Converting hardcoded values to tokens
• Creating a token governance strategy

Implementation Checklist

Copy this checklist when architecting a token system:

Token Architecture Setup:
- [ ] Audit existing values and establish naming conventions
- [ ] Define primitive tokens (raw values, context-free)
- [ ] Define semantic tokens (purpose-based, reference primitives)
- [ ] Create theme overrides (dark.json, brand variants)
- [ ] Add component tokens for complex stateful components
- [ ] Configure build output (CSS variables, Tailwind, JSON)

Quick Reference: Token Layers

Layer	Also Called	Purpose	Example
Primitive	Core, Base, Global	Raw values, context-free	blue-500: #3b82f6
Semantic	Alias, Purpose, Role	Meaning-based references	color-primary: {blue-500}
Component	Specific, Local	Component-scoped tokens	button-bg: {color-primary}

The Three-Layer Architecture

┌─────────────────────────────────────────────────────────┐
│                    COMPONENT TOKENS                      │
│        button-bg, card-border, input-focus-ring          │
│                         ↓ references                     │
├─────────────────────────────────────────────────────────┤
│                    SEMANTIC TOKENS                       │
│       color-primary, color-bg-surface, spacing-page      │
│                         ↓ references                     │
├─────────────────────────────────────────────────────────┤
│                    PRIMITIVE TOKENS                      │
│         blue-500, gray-100, spacing-16, radius-8         │
│                    (raw values only)                     │
└─────────────────────────────────────────────────────────┘

---

Layer 1: Primitive Tokens

Raw design values with no semantic meaning. These are the building blocks.

Characteristics

• Context-free (no "primary", "background", etc.)
• Named by their intrinsic property (color: hue, spacing: size)
• Never change between themes
• Comprehensive palette of options

Structure

{
  "primitive": {
    "color": {
      "gray": {
        "50": { "value": "#f9fafb" },
        "100": { "value": "#f3f4f6" },
        "200": { "value": "#e5e7eb" },
        "300": { "value": "#d1d5db" },
        "400": { "value": "#9ca3af" },
        "500": { "value": "#6b7280" },
        "600": { "value": "#4b5563" },
        "700": { "value": "#374151" },
        "800": { "value": "#1f2937" },
        "900": { "value": "#111827" },
        "950": { "value": "#030712" }
      },
      "blue": {
        "50": { "value": "#eff6ff" },
        "100": { "value": "#dbeafe" },
        "200": { "value": "#bfdbfe" },
        "300": { "value": "#93c5fd" },
        "400": { "value": "#60a5fa" },
        "500": { "value": "#3b82f6" },
        "600": { "value": "#2563eb" },
        "700": { "value": "#1d4ed8" },
        "800": { "value": "#1e40af" },
        "900": { "value": "#1e3a8a" }
      },
      "green": { /* success colors */ },
      "red": { /* error colors */ },
      "amber": { /* warning colors */ }
    },
    "spacing": {
      "0": { "value": "0" },
      "1": { "value": "0.25rem" },
      "2": { "value": "0.5rem" },
      "3": { "value": "0.75rem" },
      "4": { "value": "1rem" },
      "5": { "value": "1.25rem" },
      "6": { "value": "1.5rem" },
      "8": { "value": "2rem" },
      "10": { "value": "2.5rem" },
      "12": { "value": "3rem" },
      "16": { "value": "4rem" },
      "20": { "value": "5rem" },
      "24": { "value": "6rem" }
    },
    "radius": {
      "none": { "value": "0" },
      "sm": { "value": "0.125rem" },
      "md": { "value": "0.375rem" },
      "lg": { "value": "0.5rem" },
      "xl": { "value": "0.75rem" },
      "2xl": { "value": "1rem" },
      "full": { "value": "9999px" }
    },
    "font": {
      "family": {
        "sans": { "value": "Inter, system-ui, sans-serif" },
        "mono": { "value": "JetBrains Mono, monospace" }
      },
      "size": {
        "xs": { "value": "0.75rem" },
        "sm": { "value": "0.875rem" },
        "md": { "value": "1rem" },
        "lg": { "value": "1.125rem" },
        "xl": { "value": "1.25rem" },
        "2xl": { "value": "1.5rem" },
        "3xl": { "value": "1.875rem" },
        "4xl": { "value": "2.25rem" }
      },
      "weight": {
        "normal": { "value": "400" },
        "medium": { "value": "500" },
        "semibold": { "value": "600" },
        "bold": { "value": "700" }
      }
    }
  }
}

---

Layer 2: Semantic Tokens

Purpose-based tokens that reference primitives. These tokens change between themes.

Characteristics

• Named by purpose/role, not appearance
• Reference primitive tokens only
• The only layer that changes per theme
• Describe "what for", not "what it looks like"

Structure

{
  "semantic": {
    "color": {
      "bg": {
        "primary": { "value": "{primitive.color.gray.50}" },
        "secondary": { "value": "{primitive.color.gray.100}" },
        "tertiary": { "value": "{primitive.color.gray.200}" },
        "inverse": { "value": "{primitive.color.gray.900}" },
        "brand": { "value": "{primitive.color.blue.500}" }
      },
      "text": {
        "primary": { "value": "{primitive.color.gray.900}" },
        "secondary": { "value": "{primitive.color.gray.600}" },
        "tertiary": { "value": "{primitive.color.gray.500}" },
        "inverse": { "value": "{primitive.color.gray.50}" },
        "brand": { "value": "{primitive.color.blue.600}" },
        "link": { "value": "{primitive.color.blue.600}" }
      },
      "border": {
        "primary": { "value": "{primitive.color.gray.200}" },
        "secondary": { "value": "{primitive.color.gray.300}" },
        "focus": { "value": "{primitive.color.blue.500}" }
      },
      "status": {
        "success": { "value": "{primitive.color.green.500}" },
        "warning": { "value": "{primitive.color.amber.500}" },
        "error": { "value": "{primitive.color.red.500}" },
        "info": { "value": "{primitive.color.blue.500}" }
      },
      "interactive": {
        "primary": { "value": "{primitive.color.blue.500}" },
        "primary-hover": { "value": "{primitive.color.blue.600}" },
        "primary-active": { "value": "{primitive.color.blue.700}" },
        "secondary": { "value": "{primitive.color.gray.100}" },
        "secondary-hover": { "value": "{primitive.color.gray.200}" }
      }
    },
    "spacing": {
      "page": { "value": "{primitive.spacing.6}" },
      "section": { "value": "{primitive.spacing.12}" },
      "element": { "value": "{primitive.spacing.4}" },
      "inline": { "value": "{primitive.spacing.2}" }
    },
    "radius": {
      "interactive": { "value": "{primitive.radius.md}" },
      "container": { "value": "{primitive.radius.lg}" },
      "pill": { "value": "{primitive.radius.full}" }
    }
  }
}

Dark Theme Override

{
  "semantic": {
    "color": {
      "bg": {
        "primary": { "value": "{primitive.color.gray.950}" },
        "secondary": { "value": "{primitive.color.gray.900}" },
        "tertiary": { "value": "{primitive.color.gray.800}" },
        "inverse": { "value": "{primitive.color.gray.50}" }
      },
      "text": {
        "primary": { "value": "{primitive.color.gray.50}" },
        "secondary": { "value": "{primitive.color.gray.400}" },
        "tertiary": { "value": "{primitive.color.gray.500}" },
        "inverse": { "value": "{primitive.color.gray.900}" }
      },
      "border": {
        "primary": { "value": "{primitive.color.gray.800}" },
        "secondary": { "value": "{primitive.color.gray.700}" }
      }
    }
  }
}

---

Layer 3: Component Tokens

Component-specific tokens that reference semantic tokens. Optional but powerful for complex components.

Characteristics

• Scoped to a specific component
• Reference semantic tokens (rarely primitives)
• Enable component-level customization
• Used for complex, stateful components

Structure

{
  "component": {
    "button": {
      "primary": {
        "bg": { "value": "{semantic.color.interactive.primary}" },
        "bg-hover": { "value": "{semantic.color.interactive.primary-hover}" },
        "text": { "value": "{semantic.color.text.inverse}" },
        "border": { "value": "transparent" },
        "radius": { "value": "{semantic.radius.interactive}" },
        "padding-x": { "value": "{primitive.spacing.4}" },
        "padding-y": { "value": "{primitive.spacing.2}" }
      },
      "secondary": {
        "bg": { "value": "{semantic.color.interactive.secondary}" },
        "bg-hover": { "value": "{semantic.color.interactive.secondary-hover}" },
        "text": { "value": "{semantic.color.text.primary}" },
        "border": { "value": "{semantic.color.border.primary}" }
      },
      "disabled": {
        "bg": { "value": "{primitive.color.gray.100}" },
        "text": { "value": "{primitive.color.gray.400}" }
      }
    },
    "input": {
      "bg": { "value": "{semantic.color.bg.primary}" },
      "text": { "value": "{semantic.color.text.primary}" },
      "placeholder": { "value": "{semantic.color.text.tertiary}" },
      "border": { "value": "{semantic.color.border.primary}" },
      "border-focus": { "value": "{semantic.color.border.focus}" },
      "radius": { "value": "{semantic.radius.interactive}" },
      "padding-x": { "value": "{primitive.spacing.3}" },
      "padding-y": { "value": "{primitive.spacing.2}" }
    },
    "card": {
      "bg": { "value": "{semantic.color.bg.primary}" },
      "border": { "value": "{semantic.color.border.primary}" },
      "radius": { "value": "{semantic.radius.container}" },
      "padding": { "value": "{semantic.spacing.element}" },
      "shadow": { "value": "{primitive.shadow.md}" }
    }
  }
}

---

CSS Output

Generated Variables

/* Primitives - available but rarely used directly */
:root {
  --primitive-color-gray-50: #f9fafb;
  --primitive-color-gray-900: #111827;
  --primitive-color-blue-500: #3b82f6;
  --primitive-spacing-4: 1rem;
  /* ... */
}

/* Semantic - the main tokens you use */
:root {
  --color-bg-primary: var(--primitive-color-gray-50);
  --color-text-primary: var(--primitive-color-gray-900);
  --color-interactive-primary: var(--primitive-color-blue-500);
  --spacing-element: var(--primitive-spacing-4);
  /* ... */
}

/* Dark theme overrides semantic only */
[data-theme="dark"] {
  --color-bg-primary: var(--primitive-color-gray-950);
  --color-text-primary: var(--primitive-color-gray-50);
  /* primitives stay the same */
}

/* Component tokens (optional) */
:root {
  --button-primary-bg: var(--color-interactive-primary);
  --button-primary-text: var(--color-text-inverse);
  --card-bg: var(--color-bg-primary);
  --card-padding: var(--spacing-element);
}

Usage in Components

/* Use semantic tokens */
.card {
  background: var(--color-bg-primary);
  color: var(--color-text-primary);
  border: 1px solid var(--color-border-primary);
  padding: var(--spacing-element);
}

/* Or use component tokens if defined */
.card {
  background: var(--card-bg);
  padding: var(--card-padding);
}

/* Never use primitives directly in components */
/* ❌ Bad */
.card {
  background: var(--primitive-color-gray-50);
}

---

File Organization

Recommended Structure

tokens/
├── primitive/
│   ├── colors.json
│   ├── spacing.json
│   ├── typography.json
│   ├── radius.json
│   └── shadows.json
├── semantic/
│   ├── light.json       # Light theme semantic mappings
│   └── dark.json        # Dark theme overrides
├── component/
│   ├── button.json
│   ├── input.json
│   └── card.json
└── index.json           # Combines all for build

Flat vs Nested

Nested (Recommended for large systems):

{
  "color": {
    "bg": {
      "primary": { "value": "..." }
    }
  }
}

Output: --color-bg-primary

Flat (Simpler for small systems):

{
  "color-bg-primary": { "value": "..." }
}

Output: --color-bg-primary

---

Naming Conventions

Pattern: {category}-{property}-{variant}-{state}

Category	Examples
color	color-bg-primary, color-text-secondary
spacing	spacing-page, spacing-inline
radius	radius-interactive, radius-container
font	font-size-lg, font-weight-bold
shadow	shadow-md, shadow-lg

Semantic Naming Guidelines

Use	Avoid
color-text-primary	color-dark-gray
color-bg-surface	color-white
color-interactive-primary	color-blue
spacing-page	spacing-24px
color-status-error	color-red

---

When to Add Each Layer

Situation	Layers Needed
Simple app, single theme	Primitive + Semantic
Multi-theme (light/dark)	Primitive + Semantic (per theme)
Complex components	All three layers
Multi-brand (white-label)	All three + brand-specific overrides
Design tool sync	Primitive only to start

---

Anti-Patterns

Anti-Pattern	Problem	Solution
Semantic references semantic	Circular/complex chains	Semantic → Primitive only
Using primitives in components	Breaks theming	Use semantic tokens
Color names in semantic	Leaks visual info	Use purpose names
Too many component tokens	Maintenance burden	Only for complex states
Skipping semantic layer	Can't theme	Always have semantic layer

---

Migrating Existing Tokens

Step 1: Audit Current Usage

Find all hardcoded values and existing variables.

Step 2: Create Primitive Layer

Extract unique values into primitives.

Step 3: Create Semantic Layer

Map primitives to purposes.

Step 4: Update Components

Replace hardcoded values with semantic tokens.

Step 5: Add Themes

Create theme-specific semantic overrides.

/* Before */
.button {
  background: #3b82f6;
  color: white;
}

/* After */
.button {
  background: var(--color-interactive-primary);
  color: var(--color-text-inverse);
}