title: How to make WPF DataGrid Column Header transparent
body: <p>I am trying to make the column header of my WPF Datagrid to be transparent.</p>
  
  <p>I am able to set it to a color without problem, but I can't have it transparent. Here is what I tried:</p>
  
  <pre><code>&lt;Style x:Key="DatagridColumnHeaderStyle" TargetType="{x:Type tk:DataGridColumnHeader}"&gt;
     &lt;Setter Property="Background" Value="Transparent" /&gt;
     &lt;Setter Property="Foreground" Value="#C2C4C6" /&gt;
  &lt;/Style&gt;
  
  &lt;Style x:Key="DashboardGridStyle" TargetType="{x:Type tk:DataGrid}"&gt;
     &lt;Setter Property="ColumnHeaderStyle" Value="{StaticResource DatagridColumnHeaderStyle}" /&gt;
     &lt;Setter Property="Background" Value="Transparent" /&gt;
     &lt;Setter Property="RowBackground" Value="Transparent" /&gt;
  &lt;/Style&gt;
  
  &lt;tk:DataGrid Style="{StaticResource DashboardGridStyle}" &gt;
  ...
  &lt;/tk:DataGrid&gt;
  </code></pre>
  
  <p>With this code, it seems to take the default brush.</p>
  
  <p>What am I missing?</p>