title: Set Background Color of TabControl
body: <p>I am making a heavily skinned application. I am trying to implement a tab control in WPF. I have already began to skin the tabitems and their respective backgrounds. However, I noticed with only two tabitems on the tab control fills the remaining space with just white. What property do I have to style to change this white space? Any help is appreciated, below is a reference picture as well as my xaml.</p>
  
  <p>Picture:</p>
  
  <p><img src="https://i.stack.imgur.com/oOKcT.png" alt="white space wpf tab control"></p>
  
  <p>XAML:</p>
  
  <pre><code>&lt;TabControl Margin="0,35,0,0" Background="#1F1F1F"&gt;
              &lt;TabControl.Resources&gt;
                  &lt;Style TargetType="TabItem"&gt;
                      &lt;Setter Property="Template"&gt;
                          &lt;Setter.Value&gt;
                              &lt;ControlTemplate TargetType="TabItem"&gt;
                                  &lt;Grid Name="Panel"&gt;
                                      &lt;Border Name="Border" BorderThickness="1,1,1,0" BorderBrush="Gainsboro" CornerRadius="4,4,0,0" Margin="2,0"&gt;
                                          &lt;ContentPresenter x:Name="ContentSite"
                                          VerticalAlignment="Center"
                                          HorizontalAlignment="Center"
                                          ContentSource="Header"
                                          Margin="10,2"/&gt;
                                      &lt;/Border&gt;
                                  &lt;/Grid&gt;
                                  &lt;ControlTemplate.Triggers&gt;
                                      &lt;Trigger Property="IsSelected" Value="False"&gt;
                                          &lt;Setter TargetName="Panel" Property="Background" Value="LightGray" /&gt;
                                          &lt;Setter TargetName="Panel" Property="TextBlock.Foreground" Value="Black"&gt;&lt;/Setter&gt;
                                      &lt;/Trigger&gt;
                                      &lt;Trigger Property="IsSelected" Value="True"&gt;
                                          &lt;Setter TargetName="Panel" Property="Background" Value="#4d4d4d" /&gt;
                                          &lt;Setter TargetName="Panel" Property="TextBlock.Foreground" Value="White"&gt;&lt;/Setter&gt;
                                      &lt;/Trigger&gt;
                                  &lt;/ControlTemplate.Triggers&gt;
                              &lt;/ControlTemplate&gt;
                          &lt;/Setter.Value&gt;
                      &lt;/Setter&gt;
                  &lt;/Style&gt;
              &lt;/TabControl.Resources&gt;
              &lt;TabItem Header="Settings"&gt;
  
              &lt;/TabItem&gt;
              &lt;TabItem Header="Results"&gt;
  
              &lt;/TabItem&gt;
          &lt;/TabControl&gt;
  </code></pre>