title: Vue.js watch DOM element property outside components / app
body: <p>I have a vue component nested in a regular website.</p>
  
  <p>I would like to watch from the component if a DOM element is clicked outside of this component. this is just a regular HTML element NOT in a vue component</p>
  
  <p>I can't use <code>v-on</code>. I also tried a regular event listener but that does not work either because it cannot access the component's property...</p>
  
  <p>Is there a way to do this ?</p>