diff --git a/samples/ControlCatalog/Pages/ExpanderPage.xaml b/samples/ControlCatalog/Pages/ExpanderPage.xaml
index f9ae1c7a3c..8c8702c665 100644
--- a/samples/ControlCatalog/Pages/ExpanderPage.xaml
+++ b/samples/ControlCatalog/Pages/ExpanderPage.xaml
@@ -32,6 +32,23 @@
Expanded content
+
+
+
+
+
+ Expanded content
+
+
+
+
+ Expanded content
+
+
Rounded
diff --git a/src/Avalonia.Themes.Fluent/Accents/FluentControlResourcesDark.xaml b/src/Avalonia.Themes.Fluent/Accents/FluentControlResourcesDark.xaml
index d2738c231f..7e3c8673f5 100644
--- a/src/Avalonia.Themes.Fluent/Accents/FluentControlResourcesDark.xaml
+++ b/src/Avalonia.Themes.Fluent/Accents/FluentControlResourcesDark.xaml
@@ -308,24 +308,30 @@
+
+
+
-
+
-
+
+
+
+
diff --git a/src/Avalonia.Themes.Fluent/Accents/FluentControlResourcesLight.xaml b/src/Avalonia.Themes.Fluent/Accents/FluentControlResourcesLight.xaml
index 5a9293f7b2..7917315e19 100644
--- a/src/Avalonia.Themes.Fluent/Accents/FluentControlResourcesLight.xaml
+++ b/src/Avalonia.Themes.Fluent/Accents/FluentControlResourcesLight.xaml
@@ -305,24 +305,30 @@
+
+
+
-
+
-
+
+
+
+
diff --git a/src/Avalonia.Themes.Fluent/Controls/Expander.xaml b/src/Avalonia.Themes.Fluent/Controls/Expander.xaml
index 94aaff62db..df9de331ee 100644
--- a/src/Avalonia.Themes.Fluent/Controls/Expander.xaml
+++ b/src/Avalonia.Themes.Fluent/Controls/Expander.xaml
@@ -65,6 +65,10 @@
1,0,1,1
+
+
+
+
@@ -73,12 +77,12 @@
+ Background="{TemplateBinding Background}"
+ BorderBrush="{TemplateBinding BorderBrush}"
+ BorderThickness="{TemplateBinding BorderThickness}">
-
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
@@ -160,11 +213,11 @@
-
-
+
+
@@ -192,6 +245,7 @@