title: What's the best approach to split app.xaml?
body: <p>I have so many styles in the app.xaml file and now it's close to 5000 lines (after formatting) but it's getting harder to handle even with comments.</p>
  
  <p>What's the best way to simplify it?  Something like splitting it into multiple files then reference them.</p>
  
  <p>Thanks.</p>