title: Angular-Material2 md-button and date-picker z-index values
body: <p>I'm trying out this <a href="https://github.com/koleary94/Angular-2-Datepicker" rel="nofollow noreferrer">Angular-material2-datepicker</a>. It seems the z-index is not working correctly. In the source code, I can see the z-index is set to 10000, but not sure why it shows up behind my material md-button, which I'm not sure what's the z-index value. </p>
  
  <p>How Can I bring up the date picker? </p>
  
  <p>Thanks!</p>
  
  <p><a href="https://i.stack.imgur.com/PMJVq.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/PMJVq.png" alt="enter image description here"></a></p>