@wordpress/theme

A theming package that’s part of the WordPress Design System. It has two parts:

• Design Tokens: A comprehensive system of design tokens for colors, spacing, typography, and more
• Theme System: A flexible theming provider for consistent theming across applications

Design Tokens

In the Design Tokens Reference document there is a complete reference of all available design tokens including colors, spacing, typography, and more.

Architecture

Internally, the design system uses a tiered token architecture:

• Primitive tokens: Raw values like hex colors or pixel dimensions which are what the browsers eventually interpret. These live in the /tokens directory as JSON source files and are an internal implementation detail.
• Semantic tokens: Purpose-driven tokens with meaningful names that reference primitives and describe their intended use. These are what get exported as CSS custom properties.

This separation allows the design system to maintain consistency while providing flexibility, since primitive values can be updated without changing the semantic token names that developers use in their code.

Design Tokens

Design tokens are the visual design atoms of a design system. They are named entities that store visual design attributes like colors, spacing, typography, and shadows. They serve as a single source of truth that bridges design and development, ensuring consistency across platforms and making it easy to maintain and evolve the visual language of an application.

Rather than hardcoding values like #3858e9 or 16px throughout your code, tokens provide semantic names like --wpds-color-bg-interactive-brand-strong or --wpds-dimension-padding-surface-md that describe the purpose and context of the value. This makes code more maintainable and allows the design system to evolve. When a token’s value changes, all components using that token automatically reflect the update.

Structure

The design system follows the Design Tokens Community Group (DTCG) specification and organizes tokens into distinct types based on what kind of visual property they represent. Token definitions are stored as JSON files in the /tokens directory:

Each JSON file contains both primitive and semantic token definitions in a hierarchical structure. These files are the source of truth for the design system and are processed during the build step to generate CSS custom properties and other output formats in /src/prebuilt.

Token Naming

Semantic tokens follow a consistent naming pattern:

--wpds-<type>-<property>-<target>[-<modifier>]

Type indicates what kind of value it represents, usually mapping to a DTCG token type.

Property is the specific design property being defined.

Target is the component or element type the token applies to.

Modifier is an optional size or intensity modifier.

Color Token Modifiers

Color tokens extend the base pattern with additional modifiers for tone, emphasis, and state:

--wpds-color-<property>-<target>-<tone>[-<emphasis>][-<state>]

Tone defines the semantic intent of the color.

[!NOTE]
caution and warning represent two escalation levels of non-error severity.
Use caution for guidance or minor risks, and warning when the user must act to prevent an error.

Emphasis adjusts color strength relative to the base tone, if specified. The default is a normal emphasis.

State represents the interactive state of the element, if specified. The default is an idle state.

Theme Provider

The ThemeProvider is a React component that should wrap your application to provide design tokens and theme context to the child UI components. It accepts a set of customizable seed values and automatically generates a set of design tokens, which are exposed as CSS custom properties for use throughout the application.

import { ThemeProvider } from '@wordpress/theme';

function App() {
    return (
        <ThemeProvider color={ { primary: 'blue' } }>
            { /* Your app content */ }
        </ThemeProvider>
    );
}

The color prop accepts an object with the following optional properties:

• primary: The primary/accent seed color (default: '#3858e9')
• bg: The background seed color (default: '#f8f8f8')

Both properties accept any valid CSS color value. The theme system automatically generates appropriate color ramps and determines light/dark mode based on these seed colors.

Nesting Providers

The provider can be used recursively to override or modify the theme for a specific subtree.

<ThemeProvider color={ { bg: 'white' } }>
    { /* light-themed UI components */ }
    <ThemeProvider color={ { bg: '#1e1e1e' } }>
        { /* dark-themed UI components */ }
        <ThemeProvider color={ { primary: 'red' } }>
            { /* dark-themed with red accent */ }
        </ThemeProvider>
    </ThemeProvider>
    { /* light-themed UI components */ }
</ThemeProvider>

The ThemeProvider redefines some of the design system tokens. Components consuming semantic design system tokens will automatically follow the chosen theme. Note that the tokens are defined and inherited using the CSS cascade, and therefore the DOM tree, not the React tree. This is very important when using React portals.

Building

This package is built in two steps. When npm run build is run at the root of the repo, it will first run the “prebuild” step of this package, which is defined in the build script of this package’s package.json.

This step will:

1. Generate primitive tokens.
2. Build CSS and JavaScript token files.
3. Update the design tokens documentation.
4. Format all generated files.

The files generated in this step will all be committed to the repo.

After the prebuild step, the package will be built into its final form via the repo’s standard package build script.

Contributing to this package

This is an individual package that’s part of the Gutenberg project. The project is organized as a monorepo. It’s made up of multiple self-contained software packages, each with a specific purpose. The packages in this monorepo are published to npm and used by WordPress as well as other software projects.

To find out more about contributing to this package or Gutenberg as a whole, please read the project’s main contributor guide.