safe-wallet/packages/theme/ARCHITECTURE.md

Unified Theme System Architecture

This document explains how the unified theme system works across web (MUI) and mobile (Tamagui) platforms in the Safe Wallet monorepo.

Overview

The @safe-global/theme package serves as a single source of truth for design tokens (colors, spacing, typography, radius) across both web and mobile applications. It provides:

• Unified color palettes (light, dark, static)
• Platform-specific generators (MUI for web, Tamagui for mobile, CSS variables for web)
• Dual spacing systems (4px base for mobile, 8px base for web)
• Platform-specific color overrides (web uses different tints than mobile)

Architecture Diagram

flowchart TB
    subgraph palettes["📦 Source Palettes"]
        LP["Light Palette
        palettes/light.ts"]
        DP["Dark Palette
        palettes/dark.ts"]
        SP["Static Colors
        palettes/static.ts"]
    end

    subgraph tokens["🎨 Tokens"]
        T1["Typography"]
        T2["Spacing"]
        T3["Radius"]
    end

    subgraph generators["⚙️ Platform Generators"]
        MUI["MUI Generator
        generateMuiTheme"]
        TAMA["Tamagui Generator
        generateTamaguiTokens"]
        CSS["CSS Vars Generator
        generateCSSVars"]
    end

    subgraph overrides["🎯 Web Overrides"]
        WO["Color Overrides
        info, success, warning"]
    end

    subgraph output["📱 Platform Themes"]
        WT["Web Theme
        MUI Theme Object"]
        MT["Mobile Theme
        Tamagui Config"]
        CV["CSS Variables
        vars.css"]
    end

    subgraph apps["🚀 Applications"]
        WEB["Web App
        Next.js + MUI"]
        MOB["Mobile App
        Expo + Tamagui"]
    end

    LP --> MUI
    DP --> MUI
    SP --> MUI
    LP --> TAMA
    DP --> TAMA
    SP --> TAMA
    LP --> CSS
    DP --> CSS
    SP --> CSS

    T1 --> MUI
    T1 --> TAMA
    T2 --> MUI
    T2 --> TAMA
    T3 --> MUI
    T3 --> TAMA

    WO --> MUI
    WO --> CSS

    MUI --> WT
    TAMA --> MT
    CSS --> CV

    WT --> WEB
    CV --> WEB
    MT --> MOB

    style WO fill:#ffeb99,stroke:#ff9900,stroke-width:2px
    style LP fill:#e1f5ff,stroke:#0288d1
    style DP fill:#424242,stroke:#212121,color:#fff
    style SP fill:#f3e5f5,stroke:#7b1fa2

Directory Structure

packages/theme/
├── src/
│   ├── palettes/
│   │   ├── light.ts          # Unified light mode palette
│   │   ├── dark.ts           # Unified dark mode palette
│   │   ├── static.ts         # Theme-independent brand colors
│   │   └── types.ts          # TypeScript color palette types
│   ├── tokens/
│   │   ├── typography.ts     # Font family, sizes, weights
│   │   ├── spacing.ts        # Mobile (4px) & Web (8px) spacing
│   │   └── radius.ts         # Border radius scale
│   ├── generators/
│   │   ├── mui.ts            # MUI theme generator (web)
│   │   ├── tamagui.ts        # Tamagui theme generator (mobile)
│   │   ├── css-vars.ts       # CSS variables generator (web)
│   │   └── mui-extensions.ts # MUI TypeScript type extensions
│   └── index.ts              # Public API exports
├── package.json
├── tsconfig.json
└── README.md

How Theme Generation Works

1. Source Palettes (Base)

The unified palettes in packages/theme/src/palettes/ define colors that are mostly shared between platforms:

// packages/theme/src/palettes/light.ts
const lightPalette: ColorPalette = {
  text: { primary: '#121312', secondary: '#A1A3A7', ... },
  primary: { dark: '#3c3c3c', main: '#121312', light: '#636669' },
  success: { dark: '#1C5538', main: '#00B460', ... }, // Mobile colors
  info: { dark: '#15566A', main: '#00BFE5', ... },    // Mobile colors
  warning: { dark: '#6C2D19', main: '#FF8C00', ... }, // Mobile colors
  // ...
}

Important: The base palettes use mobile's color values for info, success, and warning.

2. Web Generator with Platform Overrides

The MUI generator (packages/theme/src/generators/mui.ts) applies web-specific overrides for colors that differ from mobile:

export function generateMuiTheme(mode: PaletteMode): Theme {
  const isDarkMode = mode === 'dark'
  const colors = isDarkMode ? darkPalette : lightPalette

  return createTheme({
    palette: {
      mode: isDarkMode ? 'dark' : 'light',
      ...colors,

      // Web-specific color overrides (different tints than mobile)
      ...(isDarkMode
        ? {
            success: { dark: '#388E3C', main: '#00B460', light: '#81C784', background: '#1F2920' },
            info: { dark: '#52BFDC', main: '#5FDDFF', light: '#B7F0FF', background: '#19252C' },
            warning: { dark: '#C04C32', main: '#FF8061', light: '#FFBC9F', background: '#2F2318' },
          }
        : {
            success: { dark: '#028D4C', main: '#00B460', light: '#D3F2E4', background: '#EFFAF1' },
            info: { dark: '#52BFDC', main: '#5FDDFF', light: '#D7F6FF', background: '#EFFCFF' },
            warning: { dark: '#C04C32', main: '#FF8061', light: '#FFBC9F', background: '#FFF1E0' },
          }),
    },
    // ... typography, spacing, component overrides
  })
}

3. CSS Variables Generator

The CSS variables generator (packages/theme/src/generators/css-vars.ts) also applies web-specific overrides:

export function generateCSSVars(): string {
  // Apply web-specific color overrides
  const webLightPalette: ColorPalette = {
    ...lightPalette,
    success: {
      /* web colors */
    },
    info: {
      /* web colors */
    },
    warning: {
      /* web colors */
    },
  }

  const webDarkPalette: ColorPalette = {
    ...darkPalette,
    success: {
      /* web colors */
    },
    info: {
      /* web colors */
    },
    warning: {
      /* web colors */
    },
  }

  // Generate CSS custom properties
  const lightVars = flattenPaletteToCSS(webLightPalette)
  const darkVars = flattenPaletteToCSS(webDarkPalette)

  // Output as :root and [data-theme="dark"] rules
}

4. Tamagui Generator (Mobile)

The Tamagui generator (packages/theme/src/generators/tamagui.ts) uses the base palettes without overrides:

export function generateTamaguiTokens() {
  return {
    color: {
      ...flattenPalette(lightPalette, { suffix: 'Light' }),
      ...flattenPalette(darkPalette, { suffix: 'Dark' }),
    },
    // ... other tokens
  }
}

Mobile uses the colors from the unified palettes directly.

Color Divergences Between Platforms

The following colors have different tints between web and mobile:

Light Mode Divergences

Color	Component	Web (Original)	Mobile (Unified Base)	Reason
error.dark	Dark error shade	#AC2C3B (medium red)	#8A1C27 (darker, less saturated)	Mobile uses darker shades
error.light	Light error shade	#FFB4BD (light pink)	#F79BA7 (different light pink)	Different tint preferences
error.background	Error background	#FFE6EA (very light pink)	#FFE0E6 (slightly different)	Web prefers warmer tints
info.main	Main info color	#5FDDFF (bright cyan)	#00BFE5 (darker cyan)	Different design language
info.dark	Dark info shade	#52BFDC	#15566A (much darker, teal-ish)	Web uses brighter tints
info.light	Light info shade	#D7F6FF (very light blue)	#78D2E7 (medium blue)	Web has lighter backgrounds
info.background	Info background	#EFFCFF (almost white)	#CEF0FD (more saturated)	Web prefers subtle backgrounds
success.dark	Dark success shade	#028D4C (bright green)	#1C5538 (darker, desaturated)	Mobile uses darker shades
success.light	Light success shade	#D3F2E4 (very light green)	#84D9A0 (medium green)	Web has lighter backgrounds
success.background	Success background	#EFFAF1 (almost white)	#CBF2DB (more saturated)	Web prefers subtle backgrounds
warning.main	Main warning color	#FF8061 (coral/salmon)	#FF8C00 (pure orange)	Web uses softer, coral tones
warning.dark	Dark warning shade	#C04C32 (reddish-orange)	#6C2D19 (dark brown)	Mobile uses very dark shades
warning.light	Light warning shade	#FFBC9F (light coral)	#F9B37C (peachy)	Different color temperature
warning.background	Warning background	#FFF1E0 (cream)	#FFECC2 (yellow-orange)	Web uses warmer, softer tones

Dark Mode Divergences

Color	Component	Web (Original)	Mobile (Unified Base)	Reason
error.dark	Dark error shade	#AC2C3B (medium red)	#FFE0E6 (very light pink!)	Mobile inverts dark/light in dark mode
error.light	Light error shade	#FFB4BD (light pink)	#4A2125 (very dark!)	Web keeps semantic meaning
error.background	Error background	#2F2527 (dark brown-red)	#4A2125 (slightly lighter)	Different background strategies
info.main	Main info color	#5FDDFF (bright cyan)	#00BFE5 (darker cyan)	Consistent with light mode
info.dark	Dark info shade	#52BFDC (bright)	#D9F4FB (very light)	Mobile inverts dark/light in dark mode
info.light	Light info shade	#B7F0FF (light)	#458898 (dark)	Web keeps semantic meaning
info.background	Info background	#19252C (dark blue-gray)	#203339 (slightly lighter)	Different background strategies
success.dark	Dark success shade	#388E3C (medium green)	#DEFDEA (very light green)	Mobile inverts dark/light in dark mode
success.light	Light success shade	#81C784 (light green)	#3B7A54 (dark green)	Web keeps semantic meaning
success.background	Success background	#1F2920 (dark green-gray)	#173026 (slightly different)	Different background strategies
warning.main	Main warning color	#FF8061 (coral)	#FF8C00 (pure orange)	Consistent with light mode
warning.dark	Dark warning shade	#C04C32 (reddish-orange)	#FFE4CB (very light)	Mobile inverts dark/light in dark mode
warning.light	Light warning shade	#FFBC9F (light coral)	#A65F34 (dark brown)	Web keeps semantic meaning
warning.background	Warning background	#2F2318 (dark brown)	#4A3621 (lighter brown)	Different background strategies

Key Insights

1. Semantic Consistency (Web): Web maintains semantic meaning where .dark is always darker than .main and .light is always lighter, regardless of light/dark mode.

2. Inversion Pattern (Mobile): Mobile inverts the .dark and .light shades in dark mode - .dark becomes light (for text/foreground), .light becomes dark (for backgrounds).

3. Tint Philosophy:

   • Web: Softer, more pastel tints with subtle backgrounds
   • Mobile: More saturated colors with stronger contrast

4. Color Temperature:

   • Web warning: Coral/salmon tones (warmer, softer)
   • Mobile warning: Pure orange (more saturated)

5. Main Color Alignment: success.main is shared (#00B460), but error.main, info.main, and warning.main differ between platforms.

6. Total Divergences: 28 color property differences (14 in light mode + 14 in dark mode) across 4 color groups: error, info, success, and warning.

Why This Architecture?

Before: Duplicated Palettes

Previously, web and mobile had separate, duplicated palette files:

apps/web/src/components/theme/lightPalette.ts
apps/web/src/components/theme/darkPalette.ts
apps/mobile/src/theme/palettes/lightPalette.ts
apps/mobile/src/theme/palettes/darkPalette.ts

Problems:

• Color definitions were duplicated
• Changes had to be made in multiple places
• Colors drifted between platforms over time
• No single source of truth

After: Unified with Platform Overrides

Now there's one set of palettes with platform-specific overrides:

packages/theme/src/palettes/light.ts        (single source)
packages/theme/src/palettes/dark.ts         (single source)
packages/theme/src/generators/mui.ts        (web overrides)
packages/theme/src/generators/css-vars.ts   (web overrides)
packages/theme/src/generators/tamagui.ts    (uses base directly)

Benefits:

• Single source of truth for most colors
• Platform-specific overrides are explicit and documented
• Changes to shared colors propagate automatically
• Type-safe with shared TypeScript interfaces

How to Modify Colors

Changing Shared Colors (Affects Both Platforms)

Edit the unified palettes:

// packages/theme/src/palettes/light.ts
const lightPalette: ColorPalette = {
  primary: { main: '#NEW_COLOR' }, // Changes both web and mobile
}

Then regenerate CSS vars for web:

yarn workspace @safe-global/web css-vars

Changing Web-Only Colors

Edit the platform overrides in generators:

// packages/theme/src/generators/mui.ts
export function generateMuiTheme(mode: PaletteMode): Theme {
  return createTheme({
    palette: {
      ...colors,
      info: { main: '#NEW_WEB_COLOR' }, // Only affects web
    },
  })
}

// packages/theme/src/generators/css-vars.ts
export function generateCSSVars(): string {
  const webLightPalette: ColorPalette = {
    ...lightPalette,
    info: { main: '#NEW_WEB_COLOR' }, // Only affects web CSS vars
  }
}

Changing Mobile-Only Colors

Edit the base palette (since mobile uses it directly):

// packages/theme/src/palettes/light.ts
const lightPalette: ColorPalette = {
  info: { main: '#NEW_MOBILE_COLOR' }, // Changes mobile
}

Then add web override to keep web unchanged:

// packages/theme/src/generators/mui.ts
info: { main: '#OLD_WEB_COLOR' }, // Preserve web color

Usage in Applications

Web (MUI)

// apps/web/src/components/theme/safeTheme.ts
import { generateMuiTheme } from '@safe-global/theme'

export const lightTheme = generateMuiTheme('light')
export const darkTheme = generateMuiTheme('dark')

Components use theme via MUI's theme system:

import { useTheme } from '@mui/material'

function MyComponent() {
  const theme = useTheme()
  return <Box bgcolor={theme.palette.info.main}>...</Box>
}

Or via CSS variables:

.my-element {
  color: var(--color-info-main);
  background: var(--color-info-background);
}

Mobile (Tamagui)

// apps/mobile/src/theme/tamagui.config.ts
import { generateTamaguiTokens, generateTamaguiThemes } from '@safe-global/theme'

const tokens = generateTamaguiTokens()
const themes = generateTamaguiThemes()

export default createTamagui({
  tokens,
  themes,
  // ...
})

Components use theme via Tamagui:

import { YStack } from 'tamagui'

function MyComponent() {
  return <YStack backgroundColor="$successMainLight">...</YStack>
}

Testing

Run tests for the theme package:

yarn workspace @safe-global/theme test

Regenerate CSS variables after palette changes:

yarn workspace @safe-global/web css-vars

Run type checking:

yarn workspace @safe-global/theme type-check

Summary

The unified theme system provides:

• ✅ Single source of truth for design tokens
• ✅ Platform-specific generators for MUI, Tamagui, and CSS variables
• ✅ Explicit color overrides for web's different tints
• ✅ Type safety across the entire system
• ✅ Automatic propagation of shared color changes
• ✅ Clear documentation of platform divergences

This architecture balances code reuse with platform-specific design requirements.