Integrations

Set up Master CSS in Lit

Guide to setting up Master CSS in your Lit project.

Create a Lit project

If you don't have a Lit project, create one first.

npm create vite@latest my-app -- --template lit-tscd my-app

Add Master CSS

Run the installer from the Lit project root. Lit uses the default Vite runtime mode so classes can be generated as components render.

npm create @master/css@rc -- --framework lit --yes

Use the runtime decorator

Master CSS styles inside a Lit shadow root need a runtime attached to that root. The installer adds this to the standard src/my-element.ts file when it exists.

import { LitElement, html } from 'lit'import { customElement } from 'lit/decorators.js'import { cssRuntime } from '@master/css-runtime'import type CSSRuntime from '@master/css-runtime'import manifest from 'virtual:master-css-manifest'import emittedGlobals from 'virtual:master-css-emitted-globals'@customElement('my-element')@cssRuntime({ manifest, emittedGlobals })export class MyElement extends LitElement {    cssRuntime?: CSSRuntime    render() {        return html`            <button class="inline-flex items-center gap:xs px:md py:xs r:lg bg:blue fg:white">                Hello Lit            </button>        `    }}

Start dev server

Run the command to start the Vite dev server.

npm run dev

Start using Master CSS

Now style elements inside your Lit templates using Master CSS syntax.

localhost:5173

Hello World


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