Method toggleStrongFocus

src/dev-app/dev-app/dev-app-layout.ts:177–181

(value = !this.state.strongFocusEnabled)

  }

  toggleStrongFocus(value = !this.state.strongFocusEnabled) {
    this.state.strongFocusEnabled = value;
    this._document.body.classList.toggle('demo-strong-focus', value);
    setAppState(this.state);
  }

  toggleZoneless(value = !this.isZoneless) {
    this.state.zoneless = value;