modified some styles

src/Shared/HandyControl_Shared/Themes/Styles/Base/ProgressButtonBaseStyle.xaml

@@ -25,6 +25,7 @@
     </Style>
 
     <Style x:Key="ProgressButtonBaseStyle" BasedOn="{StaticResource ToggleButtonBaseStyle}" TargetType="controls:ProgressButton">
+        <Setter Property="Background" Value="{DynamicResource RegionBrush}"/>
         <Setter Property="ProgressStyle" Value="{StaticResource ProgressBarFlat4ProgressButton}"/>
         <Setter Property="Template">
             <Setter.Value>