title: How to change color of MetroTabItem
body: <p>I have <code>MetroTabControl</code>, with items added programmatically (I'm using Prism) but I don't know how to change color of <code>TabItem</code> header.</p>
  
  <p>How can I do that? I'm new to Mahapps.Metro, where should I start to learn in customization?</p>