Method toggleSystemTheme

src/dev-app/dev-app/dev-app-layout.ts:167–171

(value = !this.state.systemTheme)

  }

  toggleSystemTheme(value = !this.state.systemTheme) {
    this.state.systemTheme = value;
    this._document.body.classList.toggle('demo-experimental-theme', value);
    setAppState(this.state);
  }

  toggleFullscreen() {
    this._element.nativeElement.querySelector('.demo-content')?.requestFullscreen();