title: Vue Bootstrap Form Datepicker b-form-datepicker modal occurence
body: <p>I am using the calendar component from <a href="https://bootstrap-vue.org/docs/components/form-datepicker" rel="nofollow noreferrer">https://bootstrap-vue.org/docs/components/form-datepicker</a>.</p>
  
  <p>I want to achive these two issues:  </p>
  
  <ol>
  <li><p>When the calendar modal is shown I want the other background to be darkenend/faded out. That way the user easier gains the mental focus to the widget and the date to be selected.<br>
  How to achive that?  </p></li>
  <li><p>It would also be nice to have the calendar, when displayed, to be shown in the middle of the page. Just like a modal menu.
  How to achive that?  </p></li>
  <li><p>I cannot really get an understanding of the documentation's <strong>Dark mode</strong> <a href="https://bootstrap-vue.org/docs/components/form-datepicker#dark-mode" rel="nofollow noreferrer">https://bootstrap-vue.org/docs/components/form-datepicker#dark-mode</a>.<br>
  Where and how to "<em>Set the <strong>dark</strong> prop to <strong>true</strong> to enable the dark background.</em>"?<br>
  This could sound like solving my first question...</p></li>
  </ol>
  
  <p>Thanks for any hints on solving that...</p>