title: Background does not change of button C# WPF
body: <p>I am trying to change style on mouseover.</p>
  
  <p><strong>My Code is:</strong></p>
  
  <pre><code>&lt;Button Name="register" Content="Register" Margin="15,410,20,0" Padding="6" FontSize="18" VerticalAlignment="Top" Background="#FF0090D6" BorderBrush="#FF0090D6" Foreground="White"&gt;
                      &lt;Button.Style&gt;
                          &lt;Style TargetType="Button"&gt;
                              &lt;Style.Triggers&gt;
                                  &lt;Trigger Property="IsMouseOver" Value="True"&gt;
                                      &lt;Setter Property="Background" Value="Red"&gt;&lt;/Setter&gt;
                                  &lt;/Trigger&gt;
                              &lt;/Style.Triggers&gt;
                          &lt;/Style&gt;
                      &lt;/Button.Style&gt;
                  &lt;/Button&gt;
  </code></pre>
  
  <p>But the Background is the same default thing. But when i change property to <code>BorderThickness</code> then it works.</p>
  
  <p>What am i doing wrong?</p>