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    Castor is Onfido's design system.

    Get started

    Install package

    npm install @onfido/castor

    If you plan to use icons, also install Castor Icons package:

    npm install @onfido/castor-icons

    For monospaced font we do use Roboto Mono, please use any desired way of including it in your app.

    Setup using CSS

    In order to use Castor with plain HTML + CSS, you must make its source available to public, and include castor.css and a chosen theme.

    For example, if you serve your app from "public" directory, you can copy castor.css and the themes folder from node_modules/@onfido/castor/dist to public (or your root assets folder), then include them in your HTML file:

    <link rel="stylesheet" href="./castor.css" />

    Choose one theme from the following options:

    <link rel="stylesheet" href="./themes/day.css" />
    <link rel="stylesheet" href="./themes/night.css" />

    Setup using Sass

    @use Castor within your main Sass file:

    @use '~@onfido/castor';

    One time only, choose and include one theme within your root element from the following options:

    :root {
      // "day" theme
      // OR "night" theme
      @include castor.night();

    Also include any component(s) you wish to use. For example:

    @include castor.Button();
    @include castor.Icon();
    // OR all at once, only recommended for prototyping
    @include castor.components();

    If you're using CSS modules, you must use a global scope when including components. For example, for PostCSS:

    @use '~@onfido/castor';
    :global {
      @include castor.Button();
      @include castor.Icon();

    Setup using CSS-in-JS (for example Emotion)

    Import castor.css in your root JS file:

    import '@onfido/castor/dist/castor.css';

    Choose and import one theme from the following options:

    import '@onfido/castor/dist/themes/day.css';
    import '@onfido/castor/dist/themes/night.css';

    Testing with (JS) Jest

    Castor (and its additions) are exported as ECMAScript modules targeting ECMAScript 2019. Jest will not understand the code in these modules, resulting in syntax errors.

    Jest uses Babel to transpile code before running tests. However, it does not include any files from the node_modules directory.

    You will need to adjust the transformIgnorePatterns setting to make sure Castor code does not get excluded when transpiling:

    "transformIgnorePatterns": ["node_modules/(?!@onfido/castor)"]

    Please note that due to an existing issue Jest will only support your Babel configuration named as babel.config.js.

    Switch theme

    To be able to switch between one and another, use "classed" themes when importing, and switch with the helper:

    import { switchTheme } from '@onfido/castor';
    // switch to "day" theme
    import '@onfido/castor/dist/themes/day-class.css';
    // OR to "night" theme
    import '@onfido/castor/dist/themes/night-class.css';

    You can also include class themes within your Sass file instead:

    @use '~@onfido/castor';
    @include castor.night('class');

    These themes are not applied to the root element but instead theme variables are scoped to CSS classes, which are then applied to the body element.

    You can also switch a theme on any selectable elements, for example switching on a section using the custom theme:

    .castor-theme--custom {
      // ...theme CSS variables
    switchTheme('custom', document.querySelector('.section'));

    If you do not use JavaScript, you might consider including a different CSS theme file based on URL parameter.

    Lastly, if you're extremely concerned about efficiency, you can shave off 1-3 KBs by not including base tokens twice, if they're shared between the themes you're switching:

    @use '~@onfido/castor';
    :root {
      @include castor.tokens();
    @include'class', 'raw');
    @include castor.night('class', 'raw');

    Use components

    When everything's setup using either CSS or Sass approach, you can then easily add a primary action Castor button to your HTML:

    <button class="ods-button -action--primary">Button</button>

    The appearance of this button can be changed by applying different predefined modifiers. For example, you might use the -action--secondary modifier to style it as a secondary (action) button instead.

    You can also create and use your custom modifiers using tokens.

    For example, if you'd like a round button, you can create a CSS modifier class using the "full" border-radius token:

    .ods-button.round {
      border-radius: var(--ods-border-radius-full);

    Or using the Sass helper:

    @use '~@onfido/castor';
    .ods-button.round {
      border-radius: castor.border-radius('full');
    <button class="ods-button -action--primary round">Round Button</button>

    Components have basic types exported so that you could create your own JS/TS variations using any renderer chosen (for example, Vue or Angular).

    Please note that the @onfido/castor-icons package is a peer dependency and is required to be installed for types to work properly. Yarn and newer versions of npm (using lockfile v2) will resolve it, otherwise it must be installed manually even if you don't plan to use icons.




    npm i @onfido/castor

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