name {color: red}</style>
      <h3 id="name">${this.is}</h3>
      <div>${this.headerTemplate}</div>
      [[myProp.stuffThatGoesHere]]
      <div>${this.footerTemplate}</div>
    `;
  }
  static get headerTemplate() { return html`<h1>Header</h1>`; }
  static get footerTemplate() { return html`<h1>Footer</h1>`; }
}
customElements.define(SuperClass.is, SuperClass);
class SubClass extends SuperClass {
  static get is() {return 'sub-class';}
  static get template() {
    return html`
      <style>.frame {font