element-styles.ts

import { component, JoistElement } from '@joist/component';
import { template, html } from '@joist/component/lit-html';

@component({
  tagName: 'app-root',
  shadowDom: 'open',
  state: {
   title: 'Hello World'
  },
  styles: [`
    :host {
      display: block;
    }
 
    h1 {
      color: red;
    }
  `],
  render: template(({ state }) => {
    return html`
      <h1>${state.title}</h1>
    `
  })
})
class AppElement extends JoistElement {}