Convert a Theme UI config to Figma Styles.

Install the plugin

Choose a .json file that only contains your theme. Example:

{
  "fonts": {
    "body": "-apple-system, BlinkMacSystemFont,'Segoe UI',Roboto,'Helvetica Neue',Arial,'Noto Sans',sans-serif,'Apple Color Emoji','Segoe UI Emoji','Segoe UI Symbol','Noto Color Emoji'",
    "heading": "inherit"
  },
  "fontSizes": [12, 14, 16, 20, 24, 32],
  "fontWeights": {
    "body": 400,
    "heading": 700
  },
  "lineHeights": {
    "body": 1.5,
    "heading": 1.125
  },
  "colors": {
    "text": "rgb(0,0,0)",
    "background": "#fff",
    "brand": {
      "primary": "hsl(205, 100%, 40%)",
      "secondary": "#30c"
    },
    "teal": [null, "#e6fffa", "#b2f5ea", "#81e6d9"]
  }
}

The shape of the theme has to follow the theme specification. Otherwise the plugin can't find your styles. In your frontend code you can setup your bundler to be able to load .json files so that you can directly use it for your Theme UI config. This way the file is interchangeable.

More specifically, you'll need to bring the theme into the following shape (as shown above):

• fonts, fontWeights and lineHeights have to have the same keys (above: body and heading)
• fontSizes has to be defined as Array<number>
• fontWeights and lineHeights need to have a number as property

Lastly, click "Add Styles" to create your Figma Styles.

Install the dependencies:

yarn install

And build the plugin:

yarn build

Go to your "Plugins" tab inside Figma and press the "+" button on "Development". Choose the manifest.json file inside figma-theme-ui folder.

You now can open the plugin in any project. Run yarn dev to have rollup watch your changes. You'll need to re-open the plugin after every change.

• Thanks to Figsvelte for his cool boilerplate to start a Figma plugin with Svelte
• Thanks to tailwindcss-figma-plugin for giving me an idea on how to use Figma's API