title: WPF DataGridRow BorderThickness increase row's width
body: <p>I want to display my data in DataGrid.
  I wrote my style for it and here it is</p>
  
  <pre><code>&lt;Style TargetType="DataGridColumnHeader"&gt;
      &lt;Setter Property="FontSize" Value="20"/&gt;
      &lt;Setter Property="Background" Value="DarkGreen" /&gt;
      &lt;Setter Property="Foreground" Value="White"/&gt;
      &lt;Setter Property="BorderThickness" Value="0,0,0,1"/&gt;
      &lt;Setter Property="BorderBrush" Value="ForestGreen"/&gt;
      &lt;Setter Property="Height" Value="80"/&gt;
      &lt;Setter Property="Padding" Value="5,0,0,0"/&gt;
  &lt;/Style&gt;
  
  &lt;Style TargetType="DataGridRow"&gt;
      &lt;Setter Property="FontSize" Value="18"/&gt;
      &lt;Setter Property="Background" Value="White"/&gt;
      &lt;Setter Property="Margin" Value="0,6,0,0"/&gt;
      &lt;Style.Triggers&gt;
          &lt;Trigger Property="IsMouseOver" Value="True"&gt;
              &lt;Setter Property="Background" Value="LightGreen"/&gt;
              &lt;Setter Property="Foreground" Value="DarkGreen"/&gt;
          &lt;/Trigger&gt;
          &lt;Trigger Property="IsSelected" Value="True"&gt;
              &lt;Setter Property="Background" Value="LightGreen"/&gt;
              &lt;Setter Property="Foreground" Value="DarkGreen"/&gt;
              &lt;Setter Property="BorderBrush" Value="ForestGreen"/&gt;
              &lt;Setter Property="BorderThickness" Value="1"/&gt;
          &lt;/Trigger&gt;
      &lt;/Style.Triggers&gt;
  &lt;/Style&gt;
  
  &lt;Style TargetType="DataGridCell"&gt;
      &lt;Setter Property="Height" Value="80"/&gt;
      &lt;Setter Property="VerticalContentAlignment" Value="Center"/&gt;
      &lt;Setter Property="Focusable" Value="False"/&gt;
      &lt;Style.Triggers&gt;
          &lt;Trigger Property="IsSelected" Value="True"&gt;
              &lt;Setter Property="Background" Value="LightGreen"/&gt;
              &lt;Setter Property="Foreground" Value="DarkGreen"/&gt;
              &lt;Setter Property="BorderThickness" Value="0"/&gt;
          &lt;/Trigger&gt;
      &lt;/Style.Triggers&gt;    
  &lt;/Style&gt;
  </code></pre>
  
  <p>When i select the row the border show's up but the width of the row becomes larger than the width of the DataGrid -> I don't see right part of the border and horizontal scrollbar show's up. </p>
  
  <p>So here is the question: how can i increase border thickness of the row, but do not increase row's width and height?</p>
  
  <p>UPD
  Before selection:</p>
  
  <p><img src="https://i.stack.imgur.com/xejGF.png" alt=""></p>
  
  <p>After selection:</p>
  
  <p><img src="https://i.stack.imgur.com/WwnzR.png" alt=""></p>