@bpmn-io/c4-theme

Makes bpmn.io look like the Camunda Design System (C4).

It works by re-pointing the @bpmn-io/theme semantic tokens at C4 tokens, so one import themes every bpmn.io component at once. Colour always comes from C4; the structure it implies — radii, spacing, control heights, ghost buttons — follows the shadcn/ui conventions C4 is built on.

Usage

Put .c4-ui on your application root (it carries the design system's tokens), load the base component CSS, then the shared tokens and the adapter for each component in use. The theme is scoped to .c4-ui, so importing the stylesheet is the only opt-in:

<body class="c4-ui">
  <div id="canvas"></div>
  <div id="properties-panel"></div>
</body>

import '@camunda/design-system/styles.css';
import '@bpmn-io/properties-panel/dist/assets/properties-panel.css';
import '@bpmn-io/c4-theme/assets/tokens.css';
import '@bpmn-io/c4-theme/assets/properties-panel.css';

Each adapter loads after the base CSS of the component it themes. To also theme the diagram surfaces — the palette, the search pad and the popup editor (the create, append and replace menus) — load diagram.css after the bpmn-js stylesheets:

import 'bpmn-js/dist/assets/diagram-js.css';
import 'bpmn-js/dist/assets/bpmn-js.css';
import '@bpmn-io/c4-theme/assets/tokens.css';
import '@bpmn-io/c4-theme/assets/diagram.css';

Dark mode follows the design system's own dark class — the theme carries no palette of its own, so it inherits whatever C4 resolves to.

Build and Run

Prepare the project by installing all dependencies:

npm install

Then, depending on your use-case, you may run any of the following commands:

# lint and run all tests
npm run all

# run all tests
npm test

# spin up the canonical playground to try the theme end-to-end
npm start

# capture side-by-side theme comparison screenshots into .captures/
npm run capture

To explore a narrower surface, it.only a scenario spec or spin up one of the component-specific playgrounds:

npm run start:properties-panel
npm run start:diagram
npm run start:bpmn
npm run start:dmn

License

MIT