release v1.5.5

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

@@ -133,7 +133,7 @@
 
     <Style x:Key="TabItemCapsuleBaseStyle" TargetType="TabItem">
         <Setter Property="FocusVisualStyle" Value="{x:Null}"/>
-        <Setter Property="Background" Value="{DynamicResource DefaultBrush}"/>
+        <Setter Property="Background" Value="{DynamicResource RegionBrush}"/>
         <Setter Property="BorderBrush" Value="{DynamicResource BorderBrush}"/>
         <Setter Property="Foreground" Value="{DynamicResource PrimaryTextBrush}"/>
         <Setter Property="BorderThickness" Value="1"/>