ux: new style for CheckBox:focus-visible

Signed-off-by: leo <longshuang@msn.cn>

Author: love-linger

src/Resources/Styles.axaml

@@ -1102,10 +1102,7 @@
 
     <Style Selector="^:focus-visible /template/ Border#Border">
       <Setter Property="BorderBrush" Value="{DynamicResource Brush.Accent}"/>
-      <Setter Property="Background" Value="{DynamicResource Brush.Accent}"/>
-    </Style>
-    <Style Selector="^:focus-visible /template/ Path#Icon">
-      <Setter Property="Fill" Value="White"/>
+      <Setter Property="BorderThickness" Value="2"/>
     </Style>
     <Style Selector="^:pointerover /template/ Border#Border">
       <Setter Property="BorderBrush" Value="{DynamicResource Brush.Accent}"/>