title: How to categories wpf combobox items (bound with observable collection ) & each category must display different background colors
body: <p>I am new in WPF and I have wpf application with MVVM pattern + Prism, i have a combo-box bound with observable collection type. </p>
  
  <p>Account Has : <strong>Id</strong> (PK), <strong>AccountName</strong> </p>
  
  <p>I have built some account (built In for user) having Ids from 8000 to 10000, rest are generating, via app, > 10000, by mistake some Ids &lt; 8000 has been created (not editable as running application)</p>
  
  <p>Now i need to categories items in combo box based on Id group (8000 to 10000) and (Ids > 10000) and (1 to &lt; 8000) and also wants these categories show different backgrounds in combo box.</p>
  
  <p>Thanks in advance!</p>