<Window
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    x:Class="SDKSample.ResourcesWindow"
    Title="Resources Window">
  
  <!-- Define window-scoped background color resource -->
  <Window.Resources>
    <SolidColorBrush x:Key="defaultBackground" Color="Red" />
  </Window.Resources>