From 1731f88822a6d0a4c2e5a58b69f866212e7ff7e4 Mon Sep 17 00:00:00 2001
From: Max Katz <maxkatz6@outlook.com>
Date: Tue, 2 Aug 2022 20:37:55 -0400
Subject: [PATCH] Rename Default to Simple

---
 Avalonia.sln                                  |  2 +-
 samples/BindingDemo/App.xaml                  |  2 +-
 samples/ControlCatalog/App.xaml.cs            |  2 +-
 samples/ControlCatalog/ControlCatalog.csproj  |  2 +-
 samples/ControlCatalog/MainView.xaml.cs       |  4 +-
 samples/PlatformSanityChecks/App.xaml         |  3 +-
 .../PlatformSanityChecks.csproj               |  2 +-
 samples/Previewer/App.xaml                    |  5 +-
 samples/Previewer/Previewer.csproj            |  2 +-
 samples/VirtualizationDemo/App.xaml           |  4 +-
 .../VirtualizationDemo.csproj                 |  2 +-
 .../interop/Direct3DInteropSample/App.paml    |  5 +-
 .../Direct3DInteropSample.csproj              |  2 +-
 src/Avalonia.Controls/ProgressBar.cs          |  4 -
 .../Avalonia.Diagnostics.csproj               |  2 +-
 .../Diagnostics/Views/MainWindow.xaml         |  2 +-
 .../Diagnostics/Views/MainWindow.xaml.cs      |  2 +-
 src/Avalonia.Themes.Default/DefaultTheme.xaml | 75 -------------------
 .../DefaultTheme.xaml.cs                      | 11 ---
 .../Accents/Base.xaml                         |  0
 .../Accents/BaseDark.xaml                     |  0
 .../Accents/BaseLight.xaml                    |  0
 .../ApiCompatBaseline.txt                     |  0
 .../Avalonia.Themes.Simple.csproj}            |  0
 .../Controls/AutoCompleteBox.xaml             |  0
 .../Controls/Button.xaml                      |  0
 .../Controls/ButtonSpinner.xaml               |  6 +-
 .../Controls/Calendar.xaml                    |  0
 .../Controls/CalendarButton.xaml              |  0
 .../Controls/CalendarDatePicker.xaml          |  0
 .../Controls/CalendarDayButton.xaml           |  0
 .../Controls/CalendarItem.xaml                |  0
 .../Controls/CaptionButtons.xaml              | 10 +--
 .../Controls/Carousel.xaml                    |  0
 .../Controls/CheckBox.xaml                    |  0
 .../Controls/ComboBox.xaml                    |  0
 .../Controls/ComboBoxItem.xaml                |  0
 .../Controls/ContentControl.xaml              |  0
 .../Controls/ContextMenu.xaml                 |  2 +-
 .../Controls/DataValidationErrors.xaml        |  0
 .../Controls/DatePicker.xaml                  | 22 +++---
 .../Controls/DateTimePickerShared.xaml        | 22 +++---
 .../Controls/DropDownButton.xaml              |  0
 .../Controls/EmbeddableControlRoot.xaml       |  0
 .../Controls/Expander.xaml                    | 34 ++++-----
 .../Controls/FlyoutPresenter.xaml             |  0
 .../Controls/FocusAdorner.xaml                |  0
 .../Controls/GridSplitter.xaml                |  0
 .../Controls/ItemsControl.xaml                |  0
 .../Controls/Label.xaml                       |  0
 .../Controls/ListBox.xaml                     |  0
 .../Controls/ListBoxItem.xaml                 |  0
 .../Controls/ManagedFileChooser.xaml          |  0
 .../Controls/Menu.xaml                        |  6 +-
 .../Controls/MenuFlyoutPresenter.xaml         |  2 +-
 .../Controls/MenuItem.xaml                    |  2 +-
 .../Controls/NativeMenuBar.xaml               | 10 +--
 .../Controls/NotificationCard.xaml            |  0
 .../Controls/NumericUpDown.xaml               |  0
 .../Controls/OverlayPopupHost.xaml            |  0
 .../Controls/PathIcon.xaml                    |  0
 .../Controls/PopupRoot.xaml                   |  0
 .../Controls/ProgressBar.xaml                 |  0
 .../Controls/RadioButton.xaml                 |  0
 .../Controls/RepeatButton.xaml                |  0
 .../Controls/RichTextBlock.xaml               |  0
 .../Controls/ScrollBar.xaml                   |  0
 .../Controls/ScrollViewer.xaml                |  2 +-
 .../Controls/Separator.xaml                   |  0
 .../Controls/SimpleControls.xaml              | 74 ++++++++++++++++++
 .../Controls/Slider.xaml                      |  0
 .../Controls/SplitButton.xaml                 |  8 +-
 .../Controls/SplitView.xaml                   |  0
 .../Controls/TabControl.xaml                  |  0
 .../Controls/TabItem.xaml                     |  0
 .../Controls/TabStrip.xaml                    |  0
 .../Controls/TabStripItem.xaml                |  0
 .../Controls/TextBox.xaml                     | 14 ++--
 .../Controls/TimePicker.xaml                  | 20 ++---
 .../Controls/TitleBar.xaml                    |  0
 .../Controls/ToggleButton.xaml                |  0
 .../Controls/ToggleSwitch.xaml                |  0
 .../Controls/ToolTip.xaml                     |  0
 .../Controls/TransitioningContentControl.xaml |  0
 .../Controls/TreeView.xaml                    |  0
 .../Controls/TreeViewItem.xaml                |  4 +-
 .../Controls/UserControl.xaml                 |  4 +-
 .../Controls/Window.xaml                      |  0
 .../Controls/WindowNotificationManager.xaml   |  0
 .../IBitmapToImageConverter.cs                |  2 +-
 .../InverseBooleanValueConverter.cs           |  2 +-
 .../Properties/AssemblyInfo.cs                |  3 +
 .../SimpleTheme.cs                            | 14 ++--
 .../SimpleThemeMode.cs                        |  2 +-
 .../Avalonia.Designer.HostApp.csproj          |  2 +-
 .../Utilities/UriExtensionsTests.cs           |  6 +-
 .../Avalonia.Benchmarks.csproj                |  2 +-
 .../Themes/ThemeBenchmark.cs                  |  6 +-
 .../Avalonia.DesignerSupport.TestApp/App.xaml |  6 +-
 .../Avalonia.DesignerSupport.TestApp.csproj   |  2 +-
 .../Avalonia.Direct2D1.RenderTests.csproj     |  2 +-
 .../Avalonia.LeakTests.csproj                 |  2 +-
 .../Avalonia.Markup.Xaml.UnitTests.csproj     |  2 +-
 .../Xaml/BasicTests.cs                        |  2 +-
 .../Avalonia.Skia.RenderTests.csproj          |  2 +-
 .../Avalonia.UnitTests.csproj                 |  2 +-
 tests/Avalonia.UnitTests/TestServices.cs      | 19 ++---
 .../Avalonia.UnitTests/UnitTestApplication.cs |  8 +-
 108 files changed, 220 insertions(+), 241 deletions(-)
 delete mode 100644 src/Avalonia.Themes.Default/DefaultTheme.xaml
 delete mode 100644 src/Avalonia.Themes.Default/DefaultTheme.xaml.cs
 rename src/{Avalonia.Themes.Default => Avalonia.Themes.Simple}/Accents/Base.xaml (100%)
 rename src/{Avalonia.Themes.Default => Avalonia.Themes.Simple}/Accents/BaseDark.xaml (100%)
 rename src/{Avalonia.Themes.Default => Avalonia.Themes.Simple}/Accents/BaseLight.xaml (100%)
 rename src/{Avalonia.Themes.Default => Avalonia.Themes.Simple}/ApiCompatBaseline.txt (100%)
 rename src/{Avalonia.Themes.Default/Avalonia.Themes.Default.csproj => Avalonia.Themes.Simple/Avalonia.Themes.Simple.csproj} (100%)
 rename src/{Avalonia.Themes.Default => Avalonia.Themes.Simple}/Controls/AutoCompleteBox.xaml (100%)
 rename src/{Avalonia.Themes.Default => Avalonia.Themes.Simple}/Controls/Button.xaml (100%)
 rename src/{Avalonia.Themes.Default => Avalonia.Themes.Simple}/Controls/ButtonSpinner.xaml (94%)
 rename src/{Avalonia.Themes.Default => Avalonia.Themes.Simple}/Controls/Calendar.xaml (100%)
 rename src/{Avalonia.Themes.Default => Avalonia.Themes.Simple}/Controls/CalendarButton.xaml (100%)
 rename src/{Avalonia.Themes.Default => Avalonia.Themes.Simple}/Controls/CalendarDatePicker.xaml (100%)
 rename src/{Avalonia.Themes.Default => Avalonia.Themes.Simple}/Controls/CalendarDayButton.xaml (100%)
 rename src/{Avalonia.Themes.Default => Avalonia.Themes.Simple}/Controls/CalendarItem.xaml (100%)
 rename src/{Avalonia.Themes.Default => Avalonia.Themes.Simple}/Controls/CaptionButtons.xaml (93%)
 rename src/{Avalonia.Themes.Default => Avalonia.Themes.Simple}/Controls/Carousel.xaml (100%)
 rename src/{Avalonia.Themes.Default => Avalonia.Themes.Simple}/Controls/CheckBox.xaml (100%)
 rename src/{Avalonia.Themes.Default => Avalonia.Themes.Simple}/Controls/ComboBox.xaml (100%)
 rename src/{Avalonia.Themes.Default => Avalonia.Themes.Simple}/Controls/ComboBoxItem.xaml (100%)
 rename src/{Avalonia.Themes.Default => Avalonia.Themes.Simple}/Controls/ContentControl.xaml (100%)
 rename src/{Avalonia.Themes.Default => Avalonia.Themes.Simple}/Controls/ContextMenu.xaml (95%)
 rename src/{Avalonia.Themes.Default => Avalonia.Themes.Simple}/Controls/DataValidationErrors.xaml (100%)
 rename src/{Avalonia.Themes.Default => Avalonia.Themes.Simple}/Controls/DatePicker.xaml (94%)
 rename src/{Avalonia.Themes.Default => Avalonia.Themes.Simple}/Controls/DateTimePickerShared.xaml (87%)
 rename src/{Avalonia.Themes.Default => Avalonia.Themes.Simple}/Controls/DropDownButton.xaml (100%)
 rename src/{Avalonia.Themes.Default => Avalonia.Themes.Simple}/Controls/EmbeddableControlRoot.xaml (100%)
 rename src/{Avalonia.Themes.Default => Avalonia.Themes.Simple}/Controls/Expander.xaml (88%)
 rename src/{Avalonia.Themes.Default => Avalonia.Themes.Simple}/Controls/FlyoutPresenter.xaml (100%)
 rename src/{Avalonia.Themes.Default => Avalonia.Themes.Simple}/Controls/FocusAdorner.xaml (100%)
 rename src/{Avalonia.Themes.Default => Avalonia.Themes.Simple}/Controls/GridSplitter.xaml (100%)
 rename src/{Avalonia.Themes.Default => Avalonia.Themes.Simple}/Controls/ItemsControl.xaml (100%)
 rename src/{Avalonia.Themes.Default => Avalonia.Themes.Simple}/Controls/Label.xaml (100%)
 rename src/{Avalonia.Themes.Default => Avalonia.Themes.Simple}/Controls/ListBox.xaml (100%)
 rename src/{Avalonia.Themes.Default => Avalonia.Themes.Simple}/Controls/ListBoxItem.xaml (100%)
 rename src/{Avalonia.Themes.Default => Avalonia.Themes.Simple}/Controls/ManagedFileChooser.xaml (100%)
 rename src/{Avalonia.Themes.Default => Avalonia.Themes.Simple}/Controls/Menu.xaml (95%)
 rename src/{Avalonia.Themes.Default => Avalonia.Themes.Simple}/Controls/MenuFlyoutPresenter.xaml (96%)
 rename src/{Avalonia.Themes.Default => Avalonia.Themes.Simple}/Controls/MenuItem.xaml (98%)
 rename src/{Avalonia.Themes.Default => Avalonia.Themes.Simple}/Controls/NativeMenuBar.xaml (76%)
 rename src/{Avalonia.Themes.Default => Avalonia.Themes.Simple}/Controls/NotificationCard.xaml (100%)
 rename src/{Avalonia.Themes.Default => Avalonia.Themes.Simple}/Controls/NumericUpDown.xaml (100%)
 rename src/{Avalonia.Themes.Default => Avalonia.Themes.Simple}/Controls/OverlayPopupHost.xaml (100%)
 rename src/{Avalonia.Themes.Default => Avalonia.Themes.Simple}/Controls/PathIcon.xaml (100%)
 rename src/{Avalonia.Themes.Default => Avalonia.Themes.Simple}/Controls/PopupRoot.xaml (100%)
 rename src/{Avalonia.Themes.Default => Avalonia.Themes.Simple}/Controls/ProgressBar.xaml (100%)
 rename src/{Avalonia.Themes.Default => Avalonia.Themes.Simple}/Controls/RadioButton.xaml (100%)
 rename src/{Avalonia.Themes.Default => Avalonia.Themes.Simple}/Controls/RepeatButton.xaml (100%)
 rename src/{Avalonia.Themes.Default => Avalonia.Themes.Simple}/Controls/RichTextBlock.xaml (100%)
 rename src/{Avalonia.Themes.Default => Avalonia.Themes.Simple}/Controls/ScrollBar.xaml (100%)
 rename src/{Avalonia.Themes.Default => Avalonia.Themes.Simple}/Controls/ScrollViewer.xaml (99%)
 rename src/{Avalonia.Themes.Default => Avalonia.Themes.Simple}/Controls/Separator.xaml (100%)
 create mode 100644 src/Avalonia.Themes.Simple/Controls/SimpleControls.xaml
 rename src/{Avalonia.Themes.Default => Avalonia.Themes.Simple}/Controls/Slider.xaml (100%)
 rename src/{Avalonia.Themes.Default => Avalonia.Themes.Simple}/Controls/SplitButton.xaml (98%)
 rename src/{Avalonia.Themes.Default => Avalonia.Themes.Simple}/Controls/SplitView.xaml (100%)
 rename src/{Avalonia.Themes.Default => Avalonia.Themes.Simple}/Controls/TabControl.xaml (100%)
 rename src/{Avalonia.Themes.Default => Avalonia.Themes.Simple}/Controls/TabItem.xaml (100%)
 rename src/{Avalonia.Themes.Default => Avalonia.Themes.Simple}/Controls/TabStrip.xaml (100%)
 rename src/{Avalonia.Themes.Default => Avalonia.Themes.Simple}/Controls/TabStripItem.xaml (100%)
 rename src/{Avalonia.Themes.Default => Avalonia.Themes.Simple}/Controls/TextBox.xaml (96%)
 rename src/{Avalonia.Themes.Default => Avalonia.Themes.Simple}/Controls/TimePicker.xaml (94%)
 rename src/{Avalonia.Themes.Default => Avalonia.Themes.Simple}/Controls/TitleBar.xaml (100%)
 rename src/{Avalonia.Themes.Default => Avalonia.Themes.Simple}/Controls/ToggleButton.xaml (100%)
 rename src/{Avalonia.Themes.Default => Avalonia.Themes.Simple}/Controls/ToggleSwitch.xaml (100%)
 rename src/{Avalonia.Themes.Default => Avalonia.Themes.Simple}/Controls/ToolTip.xaml (100%)
 rename src/{Avalonia.Themes.Default => Avalonia.Themes.Simple}/Controls/TransitioningContentControl.xaml (100%)
 rename src/{Avalonia.Themes.Default => Avalonia.Themes.Simple}/Controls/TreeView.xaml (100%)
 rename src/{Avalonia.Themes.Default => Avalonia.Themes.Simple}/Controls/TreeViewItem.xaml (96%)
 rename src/{Avalonia.Themes.Default => Avalonia.Themes.Simple}/Controls/UserControl.xaml (90%)
 rename src/{Avalonia.Themes.Default => Avalonia.Themes.Simple}/Controls/Window.xaml (100%)
 rename src/{Avalonia.Themes.Default => Avalonia.Themes.Simple}/Controls/WindowNotificationManager.xaml (100%)
 rename src/{Avalonia.Themes.Default => Avalonia.Themes.Simple}/IBitmapToImageConverter.cs (95%)
 rename src/{Avalonia.Themes.Default => Avalonia.Themes.Simple}/InverseBooleanValueConverter.cs (94%)
 create mode 100644 src/Avalonia.Themes.Simple/Properties/AssemblyInfo.cs
 rename src/{Avalonia.Themes.Default => Avalonia.Themes.Simple}/SimpleTheme.cs (89%)
 rename src/{Avalonia.Themes.Default => Avalonia.Themes.Simple}/SimpleThemeMode.cs (67%)

diff --git a/Avalonia.sln b/Avalonia.sln
index 4999719676..35b6b2108a 100644
--- a/Avalonia.sln
+++ b/Avalonia.sln
@@ -13,7 +13,7 @@ Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "Avalonia.Direct2D1", "src\W
 EndProject
 Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "Avalonia.Controls", "src\Avalonia.Controls\Avalonia.Controls.csproj", "{D2221C82-4A25-4583-9B43-D791E3F6820C}"
 EndProject
-Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "Avalonia.Themes.Default", "src\Avalonia.Themes.Default\Avalonia.Themes.Default.csproj", "{3E10A5FA-E8DA-48B1-AD44-6A5B6CB7750F}"
+Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "Avalonia.Themes.Simple", "src\Avalonia.Themes.Simple\Avalonia.Themes.Simple.csproj", "{3E10A5FA-E8DA-48B1-AD44-6A5B6CB7750F}"
 EndProject
 Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "Avalonia.Diagnostics", "src\Avalonia.Diagnostics\Avalonia.Diagnostics.csproj", "{7062AE20-5DCC-4442-9645-8195BDECE63E}"
 EndProject
diff --git a/samples/BindingDemo/App.xaml b/samples/BindingDemo/App.xaml
index 3e312c8685..175e838616 100644
--- a/samples/BindingDemo/App.xaml
+++ b/samples/BindingDemo/App.xaml
@@ -4,6 +4,6 @@
     x:Class="BindingDemo.App">
     <Application.Styles>
         <FluentTheme />
-        <StyleInclude Source="avares://Avalonia.Themes.Default/Accents/BaseLight.xaml"/>
+        <StyleInclude Source="avares://Avalonia.Themes.Simple/Accents/BaseLight.xaml"/>
     </Application.Styles>
 </Application>
diff --git a/samples/ControlCatalog/App.xaml.cs b/samples/ControlCatalog/App.xaml.cs
index 7ebb87094a..eb8ecc3af0 100644
--- a/samples/ControlCatalog/App.xaml.cs
+++ b/samples/ControlCatalog/App.xaml.cs
@@ -5,7 +5,7 @@ using Avalonia.Controls.ApplicationLifetimes;
 using Avalonia.Markup.Xaml;
 using Avalonia.Markup.Xaml.Styling;
 using Avalonia.Styling;
-using Avalonia.Themes.Default;
+using Avalonia.Themes.Simple;
 using Avalonia.Themes.Fluent;
 using ControlCatalog.ViewModels;
 
diff --git a/samples/ControlCatalog/ControlCatalog.csproj b/samples/ControlCatalog/ControlCatalog.csproj
index 8358fb3cd4..2654574a3e 100644
--- a/samples/ControlCatalog/ControlCatalog.csproj
+++ b/samples/ControlCatalog/ControlCatalog.csproj
@@ -29,7 +29,7 @@
     <ProjectReference Include="..\..\packages\Avalonia\Avalonia.csproj" />
     <ProjectReference Include="..\..\src\Avalonia.Controls.ColorPicker\Avalonia.Controls.ColorPicker.csproj" />
     <ProjectReference Include="..\..\src\Avalonia.Controls.DataGrid\Avalonia.Controls.DataGrid.csproj" />
-    <ProjectReference Include="..\..\src\Avalonia.Themes.Default\Avalonia.Themes.Default.csproj" />
+    <ProjectReference Include="..\..\src\Avalonia.Themes.Simple\Avalonia.Themes.Simple.csproj" />
     <ProjectReference Include="..\..\src\Avalonia.Themes.Fluent\Avalonia.Themes.Fluent.csproj" />
     <ProjectReference Include="..\MiniMvvm\MiniMvvm.csproj" />
     <ProjectReference Include="..\SampleControls\ControlSamples.csproj" />
diff --git a/samples/ControlCatalog/MainView.xaml.cs b/samples/ControlCatalog/MainView.xaml.cs
index 47d11738bc..d8d58edaf6 100644
--- a/samples/ControlCatalog/MainView.xaml.cs
+++ b/samples/ControlCatalog/MainView.xaml.cs
@@ -60,14 +60,14 @@ namespace ControlCatalog
                     }
                     else if (theme == CatalogTheme.DefaultLight)
                     {
-                        App.Default.Mode = Avalonia.Themes.Default.SimpleThemeMode.Light;
+                        App.Default.Mode = Avalonia.Themes.Simple.SimpleThemeMode.Light;
                         Application.Current.Styles[0] = App.DefaultLight;
                         Application.Current.Styles[1] = App.ColorPickerDefault;
                         Application.Current.Styles[2] = App.DataGridDefault;
                     }
                     else if (theme == CatalogTheme.DefaultDark)
                     {
-                        App.Default.Mode = Avalonia.Themes.Default.SimpleThemeMode.Dark;
+                        App.Default.Mode = Avalonia.Themes.Simple.SimpleThemeMode.Dark;
                         Application.Current.Styles[0] = App.DefaultDark;
                         Application.Current.Styles[1] = App.ColorPickerDefault;
                         Application.Current.Styles[2] = App.DataGridDefault;
diff --git a/samples/PlatformSanityChecks/App.xaml b/samples/PlatformSanityChecks/App.xaml
index 25bab6ae35..1b9d64fca6 100644
--- a/samples/PlatformSanityChecks/App.xaml
+++ b/samples/PlatformSanityChecks/App.xaml
@@ -1,6 +1,5 @@
 <Application xmlns="https://github.com/avaloniaui">
     <Application.Styles>
-        <StyleInclude Source="resm:Avalonia.Themes.Default.DefaultTheme.xaml?assembly=Avalonia.Themes.Default"/>
-        <StyleInclude Source="resm:Avalonia.Themes.Default.Accents.BaseLight.xaml?assembly=Avalonia.Themes.Default"/>
+        <SimpleTheme Mode="Light" />
     </Application.Styles>
 </Application>
diff --git a/samples/PlatformSanityChecks/PlatformSanityChecks.csproj b/samples/PlatformSanityChecks/PlatformSanityChecks.csproj
index 4f7f06b529..5c743aabdb 100644
--- a/samples/PlatformSanityChecks/PlatformSanityChecks.csproj
+++ b/samples/PlatformSanityChecks/PlatformSanityChecks.csproj
@@ -7,7 +7,7 @@
 
   <ItemGroup>
     <ProjectReference Include="..\..\src\Avalonia.Desktop\Avalonia.Desktop.csproj" />
-    <ProjectReference Include="..\..\src\Avalonia.Themes.Default\Avalonia.Themes.Default.csproj" />
+    <ProjectReference Include="..\..\src\Avalonia.Themes.Simple\Avalonia.Themes.Simple.csproj" />
     <ProjectReference Include="..\..\src\Avalonia.X11\Avalonia.X11.csproj" />
   </ItemGroup>
 
diff --git a/samples/Previewer/App.xaml b/samples/Previewer/App.xaml
index 6bae1955af..1b9d64fca6 100644
--- a/samples/Previewer/App.xaml
+++ b/samples/Previewer/App.xaml
@@ -1,6 +1,5 @@
 <Application xmlns="https://github.com/avaloniaui">
     <Application.Styles>
-        <StyleInclude Source="resm:Avalonia.Themes.Default.DefaultTheme.xaml?assembly=Avalonia.Themes.Default"/>
-        <StyleInclude Source="resm:Avalonia.Themes.Default.Accents.BaseLight.xaml?assembly=Avalonia.Themes.Default"/>
+        <SimpleTheme Mode="Light" />
     </Application.Styles>
-</Application>
\ No newline at end of file
+</Application>
diff --git a/samples/Previewer/Previewer.csproj b/samples/Previewer/Previewer.csproj
index 98560e9ab0..2cc84168dc 100644
--- a/samples/Previewer/Previewer.csproj
+++ b/samples/Previewer/Previewer.csproj
@@ -10,7 +10,7 @@
     <EmbeddedResource Include="**\*.xaml" />
   </ItemGroup>
   <ItemGroup>
-    <ProjectReference Include="..\..\src\Avalonia.Themes.Default\Avalonia.Themes.Default.csproj" />
+    <ProjectReference Include="..\..\src\Avalonia.Themes.Simple\Avalonia.Themes.Simple.csproj" />
   </ItemGroup>
   
   <Import Project="..\..\build\SampleApp.props" />
diff --git a/samples/VirtualizationDemo/App.xaml b/samples/VirtualizationDemo/App.xaml
index 3ad1dce794..0b64d0c09b 100644
--- a/samples/VirtualizationDemo/App.xaml
+++ b/samples/VirtualizationDemo/App.xaml
@@ -3,7 +3,7 @@
     xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
     x:Class="VirtualizationDemo.App">
     <Application.Styles>
-        <StyleInclude Source="avares://Avalonia.Themes.Default/DefaultTheme.xaml"/>
-        <StyleInclude Source="avares://Avalonia.Themes.Default/Accents/BaseLight.xaml"/>
+        <StyleInclude Source="avares://Avalonia.Themes.Simple/DefaultTheme.xaml"/>
+        <StyleInclude Source="avares://Avalonia.Themes.Simple/Accents/BaseLight.xaml"/>
     </Application.Styles>
 </Application>
\ No newline at end of file
diff --git a/samples/VirtualizationDemo/VirtualizationDemo.csproj b/samples/VirtualizationDemo/VirtualizationDemo.csproj
index bd6054327f..b27cfe77e8 100644
--- a/samples/VirtualizationDemo/VirtualizationDemo.csproj
+++ b/samples/VirtualizationDemo/VirtualizationDemo.csproj
@@ -5,7 +5,7 @@
   </PropertyGroup>
   <ItemGroup>
     <ProjectReference Include="..\..\src\Avalonia.Diagnostics\Avalonia.Diagnostics.csproj" />
-    <ProjectReference Include="..\..\src\Avalonia.Themes.Default\Avalonia.Themes.Default.csproj" />
+    <ProjectReference Include="..\..\src\Avalonia.Themes.Simple\Avalonia.Themes.Simple.csproj" />
     <ProjectReference Include="..\..\src\Linux\Avalonia.LinuxFramebuffer\Avalonia.LinuxFramebuffer.csproj" />
     <ProjectReference Include="..\MiniMvvm\MiniMvvm.csproj" />
   </ItemGroup>
diff --git a/samples/interop/Direct3DInteropSample/App.paml b/samples/interop/Direct3DInteropSample/App.paml
index d9630eef58..e6d77dfaf4 100644
--- a/samples/interop/Direct3DInteropSample/App.paml
+++ b/samples/interop/Direct3DInteropSample/App.paml
@@ -1,6 +1,5 @@
 <Application xmlns="https://github.com/avaloniaui">
   <Application.Styles>
-    <StyleInclude Source="resm:Avalonia.Themes.Default.DefaultTheme.xaml?assembly=Avalonia.Themes.Default"/>
-    <StyleInclude Source="resm:Avalonia.Themes.Default.Accents.BaseLight.xaml?assembly=Avalonia.Themes.Default"/>
+    <SimpleTheme Mode="Light" />
   </Application.Styles>
-</Application>
\ No newline at end of file
+</Application>
diff --git a/samples/interop/Direct3DInteropSample/Direct3DInteropSample.csproj b/samples/interop/Direct3DInteropSample/Direct3DInteropSample.csproj
index 81b94b4d09..f9ef4693d5 100644
--- a/samples/interop/Direct3DInteropSample/Direct3DInteropSample.csproj
+++ b/samples/interop/Direct3DInteropSample/Direct3DInteropSample.csproj
@@ -22,7 +22,7 @@
       </EmbeddedResource>
     </ItemGroup>
     <ItemGroup>
-        <ProjectReference Include="..\..\..\src\Avalonia.Themes.Default\Avalonia.Themes.Default.csproj" />
+        <ProjectReference Include="..\..\..\src\Avalonia.Themes.Simple\Avalonia.Themes.Simple.csproj" />
         <ProjectReference Include="..\..\..\src\Windows\Avalonia.Direct2D1\Avalonia.Direct2D1.csproj" />
         <ProjectReference Include="..\..\..\src\Windows\Avalonia.Win32\Avalonia.Win32.csproj" />
         <ProjectReference Include="..\..\MiniMvvm\MiniMvvm.csproj" />
diff --git a/src/Avalonia.Controls/ProgressBar.cs b/src/Avalonia.Controls/ProgressBar.cs
index 56b9caf085..91114628ee 100644
--- a/src/Avalonia.Controls/ProgressBar.cs
+++ b/src/Avalonia.Controls/ProgressBar.cs
@@ -119,14 +119,12 @@ namespace Avalonia.Controls
                 nameof(Percentage),
                 o => o.Percentage);
 
-        [Obsolete("To be removed when Avalonia.Themes.Default is discontinued.")]
         public static readonly DirectProperty<ProgressBar, double> IndeterminateStartingOffsetProperty =
             AvaloniaProperty.RegisterDirect<ProgressBar, double>(
                 nameof(IndeterminateStartingOffset),
                 p => p.IndeterminateStartingOffset,
                 (p, o) => p.IndeterminateStartingOffset = o);
 
-        [Obsolete("To be removed when Avalonia.Themes.Default is discontinued.")]
         public static readonly DirectProperty<ProgressBar, double> IndeterminateEndingOffsetProperty =
             AvaloniaProperty.RegisterDirect<ProgressBar, double>(
                 nameof(IndeterminateEndingOffset),
@@ -139,14 +137,12 @@ namespace Avalonia.Controls
             private set { SetAndRaise(PercentageProperty, ref _percentage, value); }
         }
         
-        [Obsolete("To be removed when Avalonia.Themes.Default is discontinued.")]
         public double IndeterminateStartingOffset
         {
             get => _indeterminateStartingOffset;
             set => SetAndRaise(IndeterminateStartingOffsetProperty, ref _indeterminateStartingOffset, value);
         }
 
-        [Obsolete("To be removed when Avalonia.Themes.Default is discontinued.")]
         public double IndeterminateEndingOffset
         {
             get => _indeterminateEndingOffset;
diff --git a/src/Avalonia.Diagnostics/Avalonia.Diagnostics.csproj b/src/Avalonia.Diagnostics/Avalonia.Diagnostics.csproj
index adddf3f57b..d719135a7f 100644
--- a/src/Avalonia.Diagnostics/Avalonia.Diagnostics.csproj
+++ b/src/Avalonia.Diagnostics/Avalonia.Diagnostics.csproj
@@ -19,7 +19,7 @@
     <ProjectReference Include="..\Markup\Avalonia.Markup\Avalonia.Markup.csproj" />
     <ProjectReference Include="..\Avalonia.Base\Avalonia.Base.csproj" />
     <ProjectReference Include="..\Avalonia.Controls\Avalonia.Controls.csproj" />
-    <ProjectReference Include="..\Avalonia.Themes.Default\Avalonia.Themes.Default.csproj" />
+    <ProjectReference Include="..\Avalonia.Themes.Simple\Avalonia.Themes.Simple.csproj" />
   </ItemGroup>
   <ItemGroup>
     <PackageReference Include="Microsoft.CodeAnalysis.CSharp.Scripting" Version="3.4.0" />
diff --git a/src/Avalonia.Diagnostics/Diagnostics/Views/MainWindow.xaml b/src/Avalonia.Diagnostics/Diagnostics/Views/MainWindow.xaml
index 004518598c..63073952ac 100644
--- a/src/Avalonia.Diagnostics/Diagnostics/Views/MainWindow.xaml
+++ b/src/Avalonia.Diagnostics/Diagnostics/Views/MainWindow.xaml
@@ -2,7 +2,7 @@
         xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
         xmlns:views="clr-namespace:Avalonia.Diagnostics.Views"
         xmlns:diag="clr-namespace:Avalonia.Diagnostics"
-        xmlns:default="using:Avalonia.Themes.Default"
+        xmlns:default="using:Avalonia.Themes.Simple"
         Title="Avalonia DevTools"
         x:Class="Avalonia.Diagnostics.Views.MainWindow"
         Theme="{StaticResource {x:Type Window}}">
diff --git a/src/Avalonia.Diagnostics/Diagnostics/Views/MainWindow.xaml.cs b/src/Avalonia.Diagnostics/Diagnostics/Views/MainWindow.xaml.cs
index 96dc929434..c81997f2cb 100644
--- a/src/Avalonia.Diagnostics/Diagnostics/Views/MainWindow.xaml.cs
+++ b/src/Avalonia.Diagnostics/Diagnostics/Views/MainWindow.xaml.cs
@@ -11,7 +11,7 @@ using Avalonia.Input;
 using Avalonia.Input.Raw;
 using Avalonia.Markup.Xaml;
 using Avalonia.Styling;
-using Avalonia.Themes.Default;
+using Avalonia.Themes.Simple;
 using Avalonia.VisualTree;
 
 namespace Avalonia.Diagnostics.Views
diff --git a/src/Avalonia.Themes.Default/DefaultTheme.xaml b/src/Avalonia.Themes.Default/DefaultTheme.xaml
deleted file mode 100644
index 8f5bea557c..0000000000
--- a/src/Avalonia.Themes.Default/DefaultTheme.xaml
+++ /dev/null
@@ -1,75 +0,0 @@
-<Styles x:Class="Avalonia.Themes.Default.DefaultTheme"
-        xmlns="https://github.com/avaloniaui"
-        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
-  <Styles.Resources>
-    <ResourceDictionary>
-      <ResourceDictionary.MergedDictionaries>
-        <ResourceInclude Source="avares://Avalonia.Themes.Default/Controls/Button.xaml" />
-        <ResourceInclude Source="avares://Avalonia.Themes.Default/Controls/RadioButton.xaml" />
-        <ResourceInclude Source="avares://Avalonia.Themes.Default/Controls/Expander.xaml" />
-        <ResourceInclude Source="avares://Avalonia.Themes.Default/Controls/RepeatButton.xaml" />
-        <ResourceInclude Source="avares://Avalonia.Themes.Default/Controls/ToggleSwitch.xaml" />
-        <ResourceInclude Source="avares://Avalonia.Themes.Default/Controls/ButtonSpinner.xaml" />
-        <ResourceInclude Source="avares://Avalonia.Themes.Default/Controls/ToggleButton.xaml" />
-        <ResourceInclude Source="avares://Avalonia.Themes.Default/Controls/DropDownButton.xaml" />
-        <ResourceInclude Source="avares://Avalonia.Themes.Default/Controls/PathIcon.xaml" />
-        <ResourceInclude Source="avares://Avalonia.Themes.Default/Controls/CheckBox.xaml" />
-        <ResourceInclude Source="avares://Avalonia.Themes.Default/Controls/ToolTip.xaml" />
-        <ResourceInclude Source="avares://Avalonia.Themes.Default/Controls/Label.xaml" />
-        <ResourceInclude Source="avares://Avalonia.Themes.Default/Controls/ComboBoxItem.xaml" />
-        <ResourceInclude Source="avares://Avalonia.Themes.Default/Controls/ComboBox.xaml" />
-        <ResourceInclude Source="avares://Avalonia.Themes.Default/Controls/Window.xaml" />
-        <ResourceInclude Source="avares://Avalonia.Themes.Default/Controls/Carousel.xaml" />
-        <ResourceInclude Source="avares://Avalonia.Themes.Default/Controls/CaptionButtons.xaml" />
-        <ResourceInclude Source="avares://Avalonia.Themes.Default/Controls/TitleBar.xaml" />
-        <ResourceInclude Source="avares://Avalonia.Themes.Default/Controls/TextBox.xaml" />
-        <ResourceInclude Source="avares://Avalonia.Themes.Default/Controls/AutoCompleteBox.xaml" />
-        <ResourceInclude Source="avares://Avalonia.Themes.Default/Controls/DataValidationErrors.xaml" />
-        <ResourceInclude Source="avares://Avalonia.Themes.Default/Controls/ContentControl.xaml" />
-        <ResourceInclude Source="avares://Avalonia.Themes.Default/Controls/FlyoutPresenter.xaml" />
-        <ResourceInclude Source="avares://Avalonia.Themes.Default/Controls/MenuFlyoutPresenter.xaml" />
-        <ResourceInclude Source="avares://Avalonia.Themes.Default/Controls/GridSplitter.xaml" />
-        <ResourceInclude Source="avares://Avalonia.Themes.Default/Controls/ItemsControl.xaml" />
-        <ResourceInclude Source="avares://Avalonia.Themes.Default/Controls/ListBoxItem.xaml" />
-        <ResourceInclude Source="avares://Avalonia.Themes.Default/Controls/ListBox.xaml" />
-        <ResourceInclude Source="avares://Avalonia.Themes.Default/Controls/ScrollBar.xaml" />
-        <ResourceInclude Source="avares://Avalonia.Themes.Default/Controls/ScrollViewer.xaml" />
-        <ResourceInclude Source="avares://Avalonia.Themes.Default/Controls/TabStrip.xaml" />
-        <ResourceInclude Source="avares://Avalonia.Themes.Default/Controls/TabStripItem.xaml" />
-        <ResourceInclude Source="avares://Avalonia.Themes.Default/Controls/TabControl.xaml" />
-        <ResourceInclude Source="avares://Avalonia.Themes.Default/Controls/TabItem.xaml" />
-        <ResourceInclude Source="avares://Avalonia.Themes.Default/Controls/PopupRoot.xaml" />
-        <ResourceInclude Source="avares://Avalonia.Themes.Default/Controls/OverlayPopupHost.xaml" />
-        <ResourceInclude Source="avares://Avalonia.Themes.Default/Controls/WindowNotificationManager.xaml" />
-        <ResourceInclude Source="avares://Avalonia.Themes.Default/Controls/EmbeddableControlRoot.xaml" />
-        <ResourceInclude Source="avares://Avalonia.Themes.Default/Controls/TransitioningContentControl.xaml" />
-        <ResourceInclude Source="avares://Avalonia.Themes.Default/Controls/TreeView.xaml" />
-        <ResourceInclude Source="avares://Avalonia.Themes.Default/Controls/TreeViewItem.xaml" />
-        <ResourceInclude Source="avares://Avalonia.Themes.Default/Controls/ProgressBar.xaml" />
-        <ResourceInclude Source="avares://Avalonia.Themes.Default/Controls/Separator.xaml" />
-        <ResourceInclude Source="avares://Avalonia.Themes.Default/Controls/Menu.xaml" />
-        <ResourceInclude Source="avares://Avalonia.Themes.Default/Controls/MenuItem.xaml" />
-        <ResourceInclude Source="avares://Avalonia.Themes.Default/Controls/ContextMenu.xaml" />
-        <ResourceInclude Source="avares://Avalonia.Themes.Default/Controls/CalendarButton.xaml" />
-        <ResourceInclude Source="avares://Avalonia.Themes.Default/Controls/CalendarDayButton.xaml" />
-        <ResourceInclude Source="avares://Avalonia.Themes.Default/Controls/CalendarItem.xaml" />
-        <ResourceInclude Source="avares://Avalonia.Themes.Default/Controls/Calendar.xaml" />
-        <ResourceInclude Source="avares://Avalonia.Themes.Default/Controls/CalendarDatePicker.xaml" />
-        <ResourceInclude Source="avares://Avalonia.Themes.Default/Controls/Slider.xaml" />
-        <ResourceInclude Source="avares://Avalonia.Themes.Default/Controls/NotificationCard.xaml" />
-        <ResourceInclude Source="avares://Avalonia.Themes.Default/Controls/NativeMenuBar.xaml" />
-        <ResourceInclude Source="avares://Avalonia.Themes.Default/Controls/NumericUpDown.xaml" />
-        <ResourceInclude Source="avares://Avalonia.Themes.Default/Controls/DateTimePickerShared.xaml" />
-        <ResourceInclude Source="avares://Avalonia.Themes.Default/Controls/DatePicker.xaml" />
-        <ResourceInclude Source="avares://Avalonia.Themes.Default/Controls/TimePicker.xaml" />
-        <ResourceInclude Source="avares://Avalonia.Themes.Default/Controls/SplitView.xaml" />
-        <ResourceInclude Source="avares://Avalonia.Themes.Default/Controls/ManagedFileChooser.xaml" />
-        <ResourceInclude Source="avares://Avalonia.Themes.Default/Controls/SplitButton.xaml" />
-        <ResourceInclude Source="avares://Avalonia.Themes.Default/Controls/RichTextBlock.xaml" />
-      </ResourceDictionary.MergedDictionaries>
-    </ResourceDictionary>
-  </Styles.Resources>
-
-  <StyleInclude Source="avares://Avalonia.Themes.Default/Controls/FocusAdorner.xaml" />
-  <StyleInclude Source="avares://Avalonia.Themes.Default/Controls/UserControl.xaml" />
-</Styles>
diff --git a/src/Avalonia.Themes.Default/DefaultTheme.xaml.cs b/src/Avalonia.Themes.Default/DefaultTheme.xaml.cs
deleted file mode 100644
index 598b418977..0000000000
--- a/src/Avalonia.Themes.Default/DefaultTheme.xaml.cs
+++ /dev/null
@@ -1,11 +0,0 @@
-using Avalonia.Styling;
-
-namespace Avalonia.Themes.Default
-{
-    /// <summary>
-    /// The default Avalonia theme.
-    /// </summary>
-    public class DefaultTheme : Styles
-    {
-    }
-}
diff --git a/src/Avalonia.Themes.Default/Accents/Base.xaml b/src/Avalonia.Themes.Simple/Accents/Base.xaml
similarity index 100%
rename from src/Avalonia.Themes.Default/Accents/Base.xaml
rename to src/Avalonia.Themes.Simple/Accents/Base.xaml
diff --git a/src/Avalonia.Themes.Default/Accents/BaseDark.xaml b/src/Avalonia.Themes.Simple/Accents/BaseDark.xaml
similarity index 100%
rename from src/Avalonia.Themes.Default/Accents/BaseDark.xaml
rename to src/Avalonia.Themes.Simple/Accents/BaseDark.xaml
diff --git a/src/Avalonia.Themes.Default/Accents/BaseLight.xaml b/src/Avalonia.Themes.Simple/Accents/BaseLight.xaml
similarity index 100%
rename from src/Avalonia.Themes.Default/Accents/BaseLight.xaml
rename to src/Avalonia.Themes.Simple/Accents/BaseLight.xaml
diff --git a/src/Avalonia.Themes.Default/ApiCompatBaseline.txt b/src/Avalonia.Themes.Simple/ApiCompatBaseline.txt
similarity index 100%
rename from src/Avalonia.Themes.Default/ApiCompatBaseline.txt
rename to src/Avalonia.Themes.Simple/ApiCompatBaseline.txt
diff --git a/src/Avalonia.Themes.Default/Avalonia.Themes.Default.csproj b/src/Avalonia.Themes.Simple/Avalonia.Themes.Simple.csproj
similarity index 100%
rename from src/Avalonia.Themes.Default/Avalonia.Themes.Default.csproj
rename to src/Avalonia.Themes.Simple/Avalonia.Themes.Simple.csproj
diff --git a/src/Avalonia.Themes.Default/Controls/AutoCompleteBox.xaml b/src/Avalonia.Themes.Simple/Controls/AutoCompleteBox.xaml
similarity index 100%
rename from src/Avalonia.Themes.Default/Controls/AutoCompleteBox.xaml
rename to src/Avalonia.Themes.Simple/Controls/AutoCompleteBox.xaml
diff --git a/src/Avalonia.Themes.Default/Controls/Button.xaml b/src/Avalonia.Themes.Simple/Controls/Button.xaml
similarity index 100%
rename from src/Avalonia.Themes.Default/Controls/Button.xaml
rename to src/Avalonia.Themes.Simple/Controls/Button.xaml
diff --git a/src/Avalonia.Themes.Default/Controls/ButtonSpinner.xaml b/src/Avalonia.Themes.Simple/Controls/ButtonSpinner.xaml
similarity index 94%
rename from src/Avalonia.Themes.Default/Controls/ButtonSpinner.xaml
rename to src/Avalonia.Themes.Simple/Controls/ButtonSpinner.xaml
index 4585fc8e56..9798e5290b 100644
--- a/src/Avalonia.Themes.Default/Controls/ButtonSpinner.xaml
+++ b/src/Avalonia.Themes.Simple/Controls/ButtonSpinner.xaml
@@ -2,7 +2,7 @@
                     xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
                     x:CompileBindings="True">
 
-  <ControlTheme x:Key="DefaultButtonSpinnerRepeatButton"
+  <ControlTheme x:Key="SimpleButtonSpinnerRepeatButton"
                 BasedOn="{StaticResource {x:Type RepeatButton}}"
                 TargetType="RepeatButton">
     <Setter Property="Background" Value="Transparent" />
@@ -38,7 +38,7 @@
                            IsVisible="{TemplateBinding ShowButtonSpinner}"
                            Rows="2">
                 <RepeatButton Name="PART_IncreaseButton"
-                              Theme="{StaticResource DefaultButtonSpinnerRepeatButton}">
+                              Theme="{StaticResource SimpleButtonSpinnerRepeatButton}">
                   <Path Width="8"
                         Height="4"
                         HorizontalAlignment="Center"
@@ -48,7 +48,7 @@
                         Stretch="Uniform" />
                 </RepeatButton>
                 <RepeatButton Name="PART_DecreaseButton"
-                              Theme="{StaticResource DefaultButtonSpinnerRepeatButton}">
+                              Theme="{StaticResource SimpleButtonSpinnerRepeatButton}">
                   <Path Width="8"
                         Height="4"
                         HorizontalAlignment="Center"
diff --git a/src/Avalonia.Themes.Default/Controls/Calendar.xaml b/src/Avalonia.Themes.Simple/Controls/Calendar.xaml
similarity index 100%
rename from src/Avalonia.Themes.Default/Controls/Calendar.xaml
rename to src/Avalonia.Themes.Simple/Controls/Calendar.xaml
diff --git a/src/Avalonia.Themes.Default/Controls/CalendarButton.xaml b/src/Avalonia.Themes.Simple/Controls/CalendarButton.xaml
similarity index 100%
rename from src/Avalonia.Themes.Default/Controls/CalendarButton.xaml
rename to src/Avalonia.Themes.Simple/Controls/CalendarButton.xaml
diff --git a/src/Avalonia.Themes.Default/Controls/CalendarDatePicker.xaml b/src/Avalonia.Themes.Simple/Controls/CalendarDatePicker.xaml
similarity index 100%
rename from src/Avalonia.Themes.Default/Controls/CalendarDatePicker.xaml
rename to src/Avalonia.Themes.Simple/Controls/CalendarDatePicker.xaml
diff --git a/src/Avalonia.Themes.Default/Controls/CalendarDayButton.xaml b/src/Avalonia.Themes.Simple/Controls/CalendarDayButton.xaml
similarity index 100%
rename from src/Avalonia.Themes.Default/Controls/CalendarDayButton.xaml
rename to src/Avalonia.Themes.Simple/Controls/CalendarDayButton.xaml
diff --git a/src/Avalonia.Themes.Default/Controls/CalendarItem.xaml b/src/Avalonia.Themes.Simple/Controls/CalendarItem.xaml
similarity index 100%
rename from src/Avalonia.Themes.Default/Controls/CalendarItem.xaml
rename to src/Avalonia.Themes.Simple/Controls/CalendarItem.xaml
diff --git a/src/Avalonia.Themes.Default/Controls/CaptionButtons.xaml b/src/Avalonia.Themes.Simple/Controls/CaptionButtons.xaml
similarity index 93%
rename from src/Avalonia.Themes.Default/Controls/CaptionButtons.xaml
rename to src/Avalonia.Themes.Simple/Controls/CaptionButtons.xaml
index adc02b7c3c..379b92ea17 100644
--- a/src/Avalonia.Themes.Default/Controls/CaptionButtons.xaml
+++ b/src/Avalonia.Themes.Simple/Controls/CaptionButtons.xaml
@@ -8,7 +8,7 @@
     </Border>
   </Design.PreviewWith>
 
-  <ControlTheme x:Key="DefaultCaptionButton"
+  <ControlTheme x:Key="SimpleCaptionButton"
                 TargetType="Button">
     <Setter Property="Background" Value="#ffe5e5e5" />
     <!--  Reusing BorderBrush to define pressed background color, as it's not used otherwise  -->
@@ -44,7 +44,7 @@
                     TextElement.FontSize="10">
           <Button x:Name="PART_FullScreenButton"
                   IsVisible="False"
-                  Theme="{StaticResource DefaultCaptionButton}">
+                  Theme="{StaticResource SimpleCaptionButton}">
             <Viewbox Width="11"
                      Margin="2">
               <Path Name="FullScreenButtonPath"
@@ -54,7 +54,7 @@
             </Viewbox>
           </Button>
           <Button x:Name="PART_MinimiseButton"
-                  Theme="{StaticResource DefaultCaptionButton}">
+                  Theme="{StaticResource SimpleCaptionButton}">
             <Viewbox Width="11"
                      Margin="2">
               <Path Data="M2048 1229v-205h-2048v205h2048z"
@@ -63,7 +63,7 @@
             </Viewbox>
           </Button>
           <Button x:Name="PART_RestoreButton"
-                  Theme="{StaticResource DefaultCaptionButton}">
+                  Theme="{StaticResource SimpleCaptionButton}">
             <Viewbox Width="11"
                      Margin="2">
               <Viewbox.RenderTransform>
@@ -78,7 +78,7 @@
           <Button x:Name="PART_CloseButton"
                   Background="#ffe81123"
                   BorderBrush="#fff1707a"
-                  Theme="{StaticResource DefaultCaptionButton}">
+                  Theme="{StaticResource SimpleCaptionButton}">
             <Viewbox Width="11"
                      Margin="2">
               <Path Data="M1169 1024l879 -879l-145 -145l-879 879l-879 -879l-145 145l879 879l-879 879l145 145l879 -879l879 879l145 -145z"
diff --git a/src/Avalonia.Themes.Default/Controls/Carousel.xaml b/src/Avalonia.Themes.Simple/Controls/Carousel.xaml
similarity index 100%
rename from src/Avalonia.Themes.Default/Controls/Carousel.xaml
rename to src/Avalonia.Themes.Simple/Controls/Carousel.xaml
diff --git a/src/Avalonia.Themes.Default/Controls/CheckBox.xaml b/src/Avalonia.Themes.Simple/Controls/CheckBox.xaml
similarity index 100%
rename from src/Avalonia.Themes.Default/Controls/CheckBox.xaml
rename to src/Avalonia.Themes.Simple/Controls/CheckBox.xaml
diff --git a/src/Avalonia.Themes.Default/Controls/ComboBox.xaml b/src/Avalonia.Themes.Simple/Controls/ComboBox.xaml
similarity index 100%
rename from src/Avalonia.Themes.Default/Controls/ComboBox.xaml
rename to src/Avalonia.Themes.Simple/Controls/ComboBox.xaml
diff --git a/src/Avalonia.Themes.Default/Controls/ComboBoxItem.xaml b/src/Avalonia.Themes.Simple/Controls/ComboBoxItem.xaml
similarity index 100%
rename from src/Avalonia.Themes.Default/Controls/ComboBoxItem.xaml
rename to src/Avalonia.Themes.Simple/Controls/ComboBoxItem.xaml
diff --git a/src/Avalonia.Themes.Default/Controls/ContentControl.xaml b/src/Avalonia.Themes.Simple/Controls/ContentControl.xaml
similarity index 100%
rename from src/Avalonia.Themes.Default/Controls/ContentControl.xaml
rename to src/Avalonia.Themes.Simple/Controls/ContentControl.xaml
diff --git a/src/Avalonia.Themes.Default/Controls/ContextMenu.xaml b/src/Avalonia.Themes.Simple/Controls/ContextMenu.xaml
similarity index 95%
rename from src/Avalonia.Themes.Default/Controls/ContextMenu.xaml
rename to src/Avalonia.Themes.Simple/Controls/ContextMenu.xaml
index baad686bd9..e99f1c5ac0 100644
--- a/src/Avalonia.Themes.Default/Controls/ContextMenu.xaml
+++ b/src/Avalonia.Themes.Simple/Controls/ContextMenu.xaml
@@ -15,7 +15,7 @@
                 BorderBrush="{TemplateBinding BorderBrush}"
                 BorderThickness="{TemplateBinding BorderThickness}"
                 CornerRadius="{TemplateBinding CornerRadius}">
-          <ScrollViewer Theme="{StaticResource DefaultMenuScrollViewer}">
+          <ScrollViewer Theme="{StaticResource SimpleMenuScrollViewer}">
             <ItemsPresenter Name="PART_ItemsPresenter"
                             ItemTemplate="{TemplateBinding ItemTemplate}"
                             Items="{TemplateBinding Items}"
diff --git a/src/Avalonia.Themes.Default/Controls/DataValidationErrors.xaml b/src/Avalonia.Themes.Simple/Controls/DataValidationErrors.xaml
similarity index 100%
rename from src/Avalonia.Themes.Default/Controls/DataValidationErrors.xaml
rename to src/Avalonia.Themes.Simple/Controls/DataValidationErrors.xaml
diff --git a/src/Avalonia.Themes.Default/Controls/DatePicker.xaml b/src/Avalonia.Themes.Simple/Controls/DatePicker.xaml
similarity index 94%
rename from src/Avalonia.Themes.Default/Controls/DatePicker.xaml
rename to src/Avalonia.Themes.Simple/Controls/DatePicker.xaml
index 8198158d5e..a6da2ad9f8 100644
--- a/src/Avalonia.Themes.Default/Controls/DatePicker.xaml
+++ b/src/Avalonia.Themes.Simple/Controls/DatePicker.xaml
@@ -42,7 +42,7 @@
   <Thickness x:Key="DatePickerHostMonthPadding">9,3,0,6</Thickness>
   <x:Double x:Key="DatePickerSpacerThemeWidth">1</x:Double>
 
-  <ControlTheme x:Key="DefaultDatePickerFlyoutButton"
+  <ControlTheme x:Key="SimpleDatePickerFlyoutButton"
                 TargetType="Button">
     <Setter Property="RenderTransform" Value="none" />
     <Setter Property="Template">
@@ -115,7 +115,7 @@
                     Foreground="{TemplateBinding Foreground}"
                     IsEnabled="{TemplateBinding IsEnabled}"
                     TemplatedControl.IsTemplateFocusTarget="True"
-                    Theme="{StaticResource DefaultDatePickerFlyoutButton}">
+                    Theme="{StaticResource SimpleDatePickerFlyoutButton}">
               <Grid Name="ButtonContentGrid"
                     ColumnDefinitions="78*,Auto,132*,Auto,78*">
                 <TextBlock Name="DayText"
@@ -200,7 +200,7 @@
             <Grid Name="PickerContainer">
               <Grid.Styles>
                 <Style Selector="DateTimePickerPanel > ListBoxItem">
-                  <Setter Property="Theme" Value="{StaticResource DefaultDateTimePickerItem}" />
+                  <Setter Property="Theme" Value="{StaticResource SimpleDateTimePickerItem}" />
                 </Style>
               </Grid.Styles>
               <!--  Column Definitions set in code, ignore here  -->
@@ -213,9 +213,9 @@
                                        ShouldLoop="True" />
                 </ScrollViewer>
                 <RepeatButton Name="MonthUpButton"
-                              Theme="{StaticResource DefaultDateTimePickerUpButton}" />
+                              Theme="{StaticResource SimpleDateTimePickerUpButton}" />
                 <RepeatButton Name="MonthDownButton"
-                              Theme="{StaticResource DefaultDateTimePickerDownButton}" />
+                              Theme="{StaticResource SimpleDateTimePickerDownButton}" />
               </Panel>
               <Panel Name="DayHost">
                 <ScrollViewer HorizontalScrollBarVisibility="Disabled"
@@ -226,9 +226,9 @@
                                        ShouldLoop="True" />
                 </ScrollViewer>
                 <RepeatButton Name="DayUpButton"
-                              Theme="{StaticResource DefaultDateTimePickerUpButton}" />
+                              Theme="{StaticResource SimpleDateTimePickerUpButton}" />
                 <RepeatButton Name="DayDownButton"
-                              Theme="{StaticResource DefaultDateTimePickerDownButton}" />
+                              Theme="{StaticResource SimpleDateTimePickerDownButton}" />
               </Panel>
               <Panel Name="YearHost">
                 <ScrollViewer HorizontalScrollBarVisibility="Disabled"
@@ -239,9 +239,9 @@
                                        ShouldLoop="False" />
                 </ScrollViewer>
                 <RepeatButton Name="YearUpButton"
-                              Theme="{StaticResource DefaultDateTimePickerUpButton}" />
+                              Theme="{StaticResource SimpleDateTimePickerUpButton}" />
                 <RepeatButton Name="YearDownButton"
-                              Theme="{StaticResource DefaultDateTimePickerDownButton}" />
+                              Theme="{StaticResource SimpleDateTimePickerDownButton}" />
               </Panel>
               <Rectangle Name="HighlightRect"
                          Grid.Column="0"
@@ -279,7 +279,7 @@
                       Height="{DynamicResource DatePickerFlyoutPresenterAcceptDismissHostGridHeight}"
                       HorizontalAlignment="Stretch"
                       VerticalAlignment="Stretch"
-                      Theme="{StaticResource DefaultDateTimePickerButton}">
+                      Theme="{StaticResource SimpleDateTimePickerButton}">
                 <Path Data="M0.5,8.5 5,13.5 15.5,3"
                       Stroke="{Binding $parent[Button].Foreground}"
                       StrokeLineCap="Round"
@@ -290,7 +290,7 @@
                       Height="{DynamicResource DatePickerFlyoutPresenterAcceptDismissHostGridHeight}"
                       HorizontalAlignment="Stretch"
                       VerticalAlignment="Stretch"
-                      Theme="{StaticResource DefaultDateTimePickerButton}">
+                      Theme="{StaticResource SimpleDateTimePickerButton}">
                 <Path Data="M2,2 14,14 M2,14 14 2"
                       Stroke="{Binding $parent[Button].Foreground}"
                       StrokeLineCap="Round"
diff --git a/src/Avalonia.Themes.Default/Controls/DateTimePickerShared.xaml b/src/Avalonia.Themes.Simple/Controls/DateTimePickerShared.xaml
similarity index 87%
rename from src/Avalonia.Themes.Default/Controls/DateTimePickerShared.xaml
rename to src/Avalonia.Themes.Simple/Controls/DateTimePickerShared.xaml
index 1e4b50ca40..5909a1abbf 100644
--- a/src/Avalonia.Themes.Default/Controls/DateTimePickerShared.xaml
+++ b/src/Avalonia.Themes.Simple/Controls/DateTimePickerShared.xaml
@@ -13,17 +13,17 @@
     <Border Width="200"
             Padding="20">
       <StackPanel Spacing="20">
-        <ListBoxItem Theme="{DynamicResource DefaultDateTimePickerItem}">Standard Item</ListBoxItem>
-        <ListBoxItem Theme="{DynamicResource DefaultDateTimePickerItem}" Classes="MonthItem">Month Item</ListBoxItem>
-        <RepeatButton Theme="{DynamicResource DefaultDateTimePickerButton}">Button</RepeatButton>
-        <RepeatButton Theme="{DynamicResource DefaultDateTimePickerUpButton}" IsVisible="True"/>
-        <RepeatButton Theme="{DynamicResource DefaultDateTimePickerDownButton}" IsVisible="True"/>
+        <ListBoxItem Theme="{DynamicResource SimpleDateTimePickerItem}">Standard Item</ListBoxItem>
+        <ListBoxItem Theme="{DynamicResource SimpleDateTimePickerItem}" Classes="MonthItem">Month Item</ListBoxItem>
+        <RepeatButton Theme="{DynamicResource SimpleDateTimePickerButton}">Button</RepeatButton>
+        <RepeatButton Theme="{DynamicResource SimpleDateTimePickerUpButton}" IsVisible="True"/>
+        <RepeatButton Theme="{DynamicResource SimpleDateTimePickerDownButton}" IsVisible="True"/>
       </StackPanel>
     </Border>
   </Design.PreviewWith>
 
   <!--  Theme for the items displayed in the selectors  -->
-  <ControlTheme x:Key="DefaultDateTimePickerItem"
+  <ControlTheme x:Key="SimpleDateTimePickerItem"
                 BasedOn="{StaticResource {x:Type ListBoxItem}}"
                 TargetType="ListBoxItem">
     <Setter Property="Padding" Value="{DynamicResource DatePickerFlyoutPresenterItemPadding}" />
@@ -47,7 +47,7 @@
   </ControlTheme>
 
   <!--  This is used for both the accept/dismiss & repeatbuttons in the presenter  -->
-  <ControlTheme x:Key="DefaultDateTimePickerButton"
+  <ControlTheme x:Key="SimpleDateTimePickerButton"
                 TargetType="Button">
     <Setter Property="Background" Value="{DynamicResource ThemeControlTransparentBrush}" />
     <Setter Property="Height" Value="22" />
@@ -91,8 +91,8 @@
     </Style>
   </ControlTheme>
 
-  <ControlTheme x:Key="DefaultDateTimePickerUpButton"
-                BasedOn="{StaticResource DefaultDateTimePickerButton}"
+  <ControlTheme x:Key="SimpleDateTimePickerUpButton"
+                BasedOn="{StaticResource SimpleDateTimePickerButton}"
                 TargetType="RepeatButton">
     <Setter Property="VerticalAlignment" Value="Top" />
     <Setter Property="Height" Value="22" />
@@ -114,8 +114,8 @@
     </Setter>
   </ControlTheme>
 
-  <ControlTheme x:Key="DefaultDateTimePickerDownButton"
-                BasedOn="{StaticResource DefaultDateTimePickerButton}"
+  <ControlTheme x:Key="SimpleDateTimePickerDownButton"
+                BasedOn="{StaticResource SimpleDateTimePickerButton}"
                 TargetType="RepeatButton">
     <Setter Property="VerticalAlignment" Value="Bottom" />
     <Setter Property="Height" Value="22" />
diff --git a/src/Avalonia.Themes.Default/Controls/DropDownButton.xaml b/src/Avalonia.Themes.Simple/Controls/DropDownButton.xaml
similarity index 100%
rename from src/Avalonia.Themes.Default/Controls/DropDownButton.xaml
rename to src/Avalonia.Themes.Simple/Controls/DropDownButton.xaml
diff --git a/src/Avalonia.Themes.Default/Controls/EmbeddableControlRoot.xaml b/src/Avalonia.Themes.Simple/Controls/EmbeddableControlRoot.xaml
similarity index 100%
rename from src/Avalonia.Themes.Default/Controls/EmbeddableControlRoot.xaml
rename to src/Avalonia.Themes.Simple/Controls/EmbeddableControlRoot.xaml
diff --git a/src/Avalonia.Themes.Default/Controls/Expander.xaml b/src/Avalonia.Themes.Simple/Controls/Expander.xaml
similarity index 88%
rename from src/Avalonia.Themes.Default/Controls/Expander.xaml
rename to src/Avalonia.Themes.Simple/Controls/Expander.xaml
index bfa5fb3130..9920c9445a 100644
--- a/src/Avalonia.Themes.Default/Controls/Expander.xaml
+++ b/src/Avalonia.Themes.Simple/Controls/Expander.xaml
@@ -44,7 +44,7 @@
     </Border>
   </Design.PreviewWith>
 
-  <ControlTheme x:Key="DefaultExpanderToggleButtonTheme"
+  <ControlTheme x:Key="SimpleExpanderToggleButtonTheme"
                 TargetType="ToggleButton">
     <Setter Property="HorizontalContentAlignment" Value="Stretch" />
     <Setter Property="Background" Value="Transparent" />
@@ -80,8 +80,8 @@
       <Setter Property="BorderBrush" Value="{DynamicResource ThemeBorderLowBrush}" />
     </Style>
   </ControlTheme>
-  <ControlTheme x:Key="DefaultExpanderToggleButtonUpTheme"
-                BasedOn="{StaticResource DefaultExpanderToggleButtonTheme}"
+  <ControlTheme x:Key="SimpleExpanderToggleButtonUpTheme"
+                BasedOn="{StaticResource SimpleExpanderToggleButtonTheme}"
                 TargetType="ToggleButton">
     <Style Selector="^ /template/ Path">
       <Setter Property="RenderTransform">
@@ -89,8 +89,8 @@
       </Setter>
     </Style>
   </ControlTheme>
-  <ControlTheme x:Key="DefaultExpanderToggleButtonDownTheme"
-                BasedOn="{StaticResource DefaultExpanderToggleButtonTheme}"
+  <ControlTheme x:Key="SimpleExpanderToggleButtonDownTheme"
+                BasedOn="{StaticResource SimpleExpanderToggleButtonTheme}"
                 TargetType="ToggleButton">
     <Style Selector="^ /template/ Path">
       <Setter Property="RenderTransform">
@@ -98,8 +98,8 @@
       </Setter>
     </Style>
   </ControlTheme>
-  <ControlTheme x:Key="DefaultExpanderToggleButtonLeftTheme"
-                BasedOn="{StaticResource DefaultExpanderToggleButtonTheme}"
+  <ControlTheme x:Key="SimpleExpanderToggleButtonLeftTheme"
+                BasedOn="{StaticResource SimpleExpanderToggleButtonTheme}"
                 TargetType="ToggleButton">
     <Style Selector="^ /template/ Path">
       <Setter Property="RenderTransform">
@@ -107,8 +107,8 @@
       </Setter>
     </Style>
   </ControlTheme>
-  <ControlTheme x:Key="DefaultExpanderToggleButtonRightTheme"
-                BasedOn="{StaticResource DefaultExpanderToggleButtonTheme}"
+  <ControlTheme x:Key="SimpleExpanderToggleButtonRightTheme"
+                BasedOn="{StaticResource SimpleExpanderToggleButtonTheme}"
                 TargetType="ToggleButton">
     <Style Selector="^ /template/ Path">
       <Setter Property="RenderTransform">
@@ -139,7 +139,7 @@
                             Content="{TemplateBinding Header}"
                             IsChecked="{TemplateBinding IsExpanded,
                                                         Mode=TwoWay}"
-                            Theme="{StaticResource DefaultExpanderToggleButtonRightTheme}" />
+                            Theme="{StaticResource SimpleExpanderToggleButtonRightTheme}" />
               <ContentPresenter Name="PART_ContentPresenter"
                                 Grid.Row="1"
                                 Padding="{TemplateBinding Padding}"
@@ -153,7 +153,7 @@
         </ControlTemplate>
       </Setter>
       <Style Selector="^:expanded /template/ ToggleButton#PART_toggle">
-        <Setter Property="Theme" Value="{StaticResource DefaultExpanderToggleButtonDownTheme}" />
+        <Setter Property="Theme" Value="{StaticResource SimpleExpanderToggleButtonDownTheme}" />
       </Style>
     </Style>
     <Style Selector="^[ExpandDirection=Up]">
@@ -171,7 +171,7 @@
                             Content="{TemplateBinding Header}"
                             IsChecked="{TemplateBinding IsExpanded,
                                                         Mode=TwoWay}"
-                            Theme="{StaticResource DefaultExpanderToggleButtonRightTheme}" />
+                            Theme="{StaticResource SimpleExpanderToggleButtonRightTheme}" />
               <ContentPresenter Name="PART_ContentPresenter"
                                 Grid.Row="0"
                                 Padding="{TemplateBinding Padding}"
@@ -185,7 +185,7 @@
         </ControlTemplate>
       </Setter>
       <Style Selector="^:expanded /template/ ToggleButton#PART_toggle">
-        <Setter Property="Theme" Value="{StaticResource DefaultExpanderToggleButtonUpTheme}" />
+        <Setter Property="Theme" Value="{StaticResource SimpleExpanderToggleButtonUpTheme}" />
       </Style>
     </Style>
     <Style Selector="^[ExpandDirection=Right]">
@@ -203,7 +203,7 @@
                             Content="{TemplateBinding Header}"
                             IsChecked="{TemplateBinding IsExpanded,
                                                         Mode=TwoWay}"
-                            Theme="{StaticResource DefaultExpanderToggleButtonLeftTheme}" />
+                            Theme="{StaticResource SimpleExpanderToggleButtonLeftTheme}" />
               <ContentPresenter Name="PART_ContentPresenter"
                                 Grid.Column="1"
                                 Padding="{TemplateBinding Padding}"
@@ -217,7 +217,7 @@
         </ControlTemplate>
       </Setter>
       <Style Selector="^:expanded /template/ ToggleButton#PART_toggle">
-        <Setter Property="Theme" Value="{StaticResource DefaultExpanderToggleButtonRightTheme}" />
+        <Setter Property="Theme" Value="{StaticResource SimpleExpanderToggleButtonRightTheme}" />
       </Style>
     </Style>
     <Style Selector="^[ExpandDirection=Left]">
@@ -235,7 +235,7 @@
                             Content="{TemplateBinding Header}"
                             IsChecked="{TemplateBinding IsExpanded,
                                                         Mode=TwoWay}"
-                            Theme="{StaticResource DefaultExpanderToggleButtonRightTheme}" />
+                            Theme="{StaticResource SimpleExpanderToggleButtonRightTheme}" />
               <ContentPresenter Name="PART_ContentPresenter"
                                 Grid.Column="0"
                                 Padding="{TemplateBinding Padding}"
@@ -249,7 +249,7 @@
         </ControlTemplate>
       </Setter>
       <Style Selector="^:expanded /template/ ToggleButton#PART_toggle">
-        <Setter Property="Theme" Value="{StaticResource DefaultExpanderToggleButtonLeftTheme}" />
+        <Setter Property="Theme" Value="{StaticResource SimpleExpanderToggleButtonLeftTheme}" />
       </Style>
     </Style>
   </ControlTheme>
diff --git a/src/Avalonia.Themes.Default/Controls/FlyoutPresenter.xaml b/src/Avalonia.Themes.Simple/Controls/FlyoutPresenter.xaml
similarity index 100%
rename from src/Avalonia.Themes.Default/Controls/FlyoutPresenter.xaml
rename to src/Avalonia.Themes.Simple/Controls/FlyoutPresenter.xaml
diff --git a/src/Avalonia.Themes.Default/Controls/FocusAdorner.xaml b/src/Avalonia.Themes.Simple/Controls/FocusAdorner.xaml
similarity index 100%
rename from src/Avalonia.Themes.Default/Controls/FocusAdorner.xaml
rename to src/Avalonia.Themes.Simple/Controls/FocusAdorner.xaml
diff --git a/src/Avalonia.Themes.Default/Controls/GridSplitter.xaml b/src/Avalonia.Themes.Simple/Controls/GridSplitter.xaml
similarity index 100%
rename from src/Avalonia.Themes.Default/Controls/GridSplitter.xaml
rename to src/Avalonia.Themes.Simple/Controls/GridSplitter.xaml
diff --git a/src/Avalonia.Themes.Default/Controls/ItemsControl.xaml b/src/Avalonia.Themes.Simple/Controls/ItemsControl.xaml
similarity index 100%
rename from src/Avalonia.Themes.Default/Controls/ItemsControl.xaml
rename to src/Avalonia.Themes.Simple/Controls/ItemsControl.xaml
diff --git a/src/Avalonia.Themes.Default/Controls/Label.xaml b/src/Avalonia.Themes.Simple/Controls/Label.xaml
similarity index 100%
rename from src/Avalonia.Themes.Default/Controls/Label.xaml
rename to src/Avalonia.Themes.Simple/Controls/Label.xaml
diff --git a/src/Avalonia.Themes.Default/Controls/ListBox.xaml b/src/Avalonia.Themes.Simple/Controls/ListBox.xaml
similarity index 100%
rename from src/Avalonia.Themes.Default/Controls/ListBox.xaml
rename to src/Avalonia.Themes.Simple/Controls/ListBox.xaml
diff --git a/src/Avalonia.Themes.Default/Controls/ListBoxItem.xaml b/src/Avalonia.Themes.Simple/Controls/ListBoxItem.xaml
similarity index 100%
rename from src/Avalonia.Themes.Default/Controls/ListBoxItem.xaml
rename to src/Avalonia.Themes.Simple/Controls/ListBoxItem.xaml
diff --git a/src/Avalonia.Themes.Default/Controls/ManagedFileChooser.xaml b/src/Avalonia.Themes.Simple/Controls/ManagedFileChooser.xaml
similarity index 100%
rename from src/Avalonia.Themes.Default/Controls/ManagedFileChooser.xaml
rename to src/Avalonia.Themes.Simple/Controls/ManagedFileChooser.xaml
diff --git a/src/Avalonia.Themes.Default/Controls/Menu.xaml b/src/Avalonia.Themes.Simple/Controls/Menu.xaml
similarity index 95%
rename from src/Avalonia.Themes.Default/Controls/Menu.xaml
rename to src/Avalonia.Themes.Simple/Controls/Menu.xaml
index c698343d83..95b259bfa6 100644
--- a/src/Avalonia.Themes.Default/Controls/Menu.xaml
+++ b/src/Avalonia.Themes.Simple/Controls/Menu.xaml
@@ -2,7 +2,7 @@
                     xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
                     xmlns:sys="using:System">
 
-  <ControlTheme x:Key="DefaultTopLevelMenuItem"
+  <ControlTheme x:Key="SimpleTopLevelMenuItem"
                 TargetType="MenuItem">
     <Setter Property="Background" Value="Transparent" />
     <Setter Property="Padding" Value="6 0" />
@@ -32,7 +32,7 @@
               <Border Background="{DynamicResource ThemeBackgroundBrush}"
                       BorderBrush="{DynamicResource ThemeBorderMidBrush}"
                       BorderThickness="{TemplateBinding BorderThickness}">
-                <ScrollViewer Theme="{StaticResource DefaultMenuScrollViewer}">
+                <ScrollViewer Theme="{StaticResource SimpleMenuScrollViewer}">
                   <ItemsPresenter Name="PART_ItemsPresenter"
                                   Margin="2"
                                   Grid.IsSharedSizeScope="True"
@@ -63,7 +63,7 @@
 
   <ControlTheme x:Key="{x:Type Menu}"
                 TargetType="Menu">
-    <Setter Property="ItemContainerTheme" Value="{StaticResource DefaultTopLevelMenuItem}" />
+    <Setter Property="ItemContainerTheme" Value="{StaticResource SimpleTopLevelMenuItem}" />
     <Setter Property="Template">
       <ControlTemplate>
         <Border Padding="{TemplateBinding Padding}"
diff --git a/src/Avalonia.Themes.Default/Controls/MenuFlyoutPresenter.xaml b/src/Avalonia.Themes.Simple/Controls/MenuFlyoutPresenter.xaml
similarity index 96%
rename from src/Avalonia.Themes.Default/Controls/MenuFlyoutPresenter.xaml
rename to src/Avalonia.Themes.Simple/Controls/MenuFlyoutPresenter.xaml
index 78c3d767a3..d974c36d31 100644
--- a/src/Avalonia.Themes.Default/Controls/MenuFlyoutPresenter.xaml
+++ b/src/Avalonia.Themes.Simple/Controls/MenuFlyoutPresenter.xaml
@@ -15,7 +15,7 @@
                 BorderThickness="{TemplateBinding BorderThickness}"
                 CornerRadius="{TemplateBinding CornerRadius}">
           <ScrollViewer HorizontalScrollBarVisibility="{TemplateBinding ScrollViewer.HorizontalScrollBarVisibility}"
-                        Theme="{StaticResource DefaultMenuScrollViewer}"
+                        Theme="{StaticResource SimpleMenuScrollViewer}"
                         VerticalScrollBarVisibility="{TemplateBinding ScrollViewer.VerticalScrollBarVisibility}">
             <ItemsPresenter Name="PART_ItemsPresenter"
                             Margin="{TemplateBinding Padding}"
diff --git a/src/Avalonia.Themes.Default/Controls/MenuItem.xaml b/src/Avalonia.Themes.Simple/Controls/MenuItem.xaml
similarity index 98%
rename from src/Avalonia.Themes.Default/Controls/MenuItem.xaml
rename to src/Avalonia.Themes.Simple/Controls/MenuItem.xaml
index b2d0f3535a..ec22ee413d 100644
--- a/src/Avalonia.Themes.Default/Controls/MenuItem.xaml
+++ b/src/Avalonia.Themes.Simple/Controls/MenuItem.xaml
@@ -68,7 +68,7 @@
               <Border Background="{DynamicResource ThemeBackgroundBrush}"
                       BorderBrush="{DynamicResource ThemeBorderMidBrush}"
                       BorderThickness="{TemplateBinding BorderThickness}">
-                <ScrollViewer Theme="{StaticResource DefaultMenuScrollViewer}">
+                <ScrollViewer Theme="{StaticResource SimpleMenuScrollViewer}">
                   <ItemsPresenter Name="PART_ItemsPresenter"
                                   Margin="2"
                                   Grid.IsSharedSizeScope="True"
diff --git a/src/Avalonia.Themes.Default/Controls/NativeMenuBar.xaml b/src/Avalonia.Themes.Simple/Controls/NativeMenuBar.xaml
similarity index 76%
rename from src/Avalonia.Themes.Default/Controls/NativeMenuBar.xaml
rename to src/Avalonia.Themes.Simple/Controls/NativeMenuBar.xaml
index 3c74e2743a..8c51ec8609 100644
--- a/src/Avalonia.Themes.Default/Controls/NativeMenuBar.xaml
+++ b/src/Avalonia.Themes.Simple/Controls/NativeMenuBar.xaml
@@ -1,14 +1,14 @@
 <ResourceDictionary xmlns="https://github.com/avaloniaui"
                     xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
-                    xmlns:default="clr-namespace:Avalonia.Themes.Default">
-  <default:InverseBooleanValueConverter x:Key="AvaloniaThemesDefaultNativeMenuBarInverseBooleanValueConverter"
+                    xmlns:default="clr-namespace:Avalonia.Themes.Simple">
+  <default:InverseBooleanValueConverter x:Key="AvaloniaThemesSimpleNativeMenuBarInverseBooleanValueConverter"
                                         Default="True" />
-  <default:IBitmapToImageConverter x:Key="AvaloniaThemesDefaultNativeMenuBarIBitmapToImageConverter" />
+  <default:IBitmapToImageConverter x:Key="AvaloniaThemesSimpleNativeMenuBarIBitmapToImageConverter" />
   <ControlTheme x:Key="{x:Type NativeMenuBar}"
                 TargetType="NativeMenuBar">
     <Setter Property="Template">
       <ControlTemplate>
-        <Menu IsVisible="{Binding $parent[TopLevel].(NativeMenu.IsNativeMenuExported), Converter={StaticResource AvaloniaThemesDefaultNativeMenuBarInverseBooleanValueConverter}}"
+        <Menu IsVisible="{Binding $parent[TopLevel].(NativeMenu.IsNativeMenuExported), Converter={StaticResource AvaloniaThemesSimpleNativeMenuBarInverseBooleanValueConverter}}"
               Items="{Binding $parent[TopLevel].(NativeMenu.Menu).Items}">
           <Menu.Styles>
             <Style Selector="MenuItem">
@@ -20,7 +20,7 @@
               <Setter Property="CommandParameter" Value="{Binding CommandParameter}" />
               <Setter Property="(NativeMenuBar.EnableMenuItemClickForwarding)" Value="True" />
               <!--  NativeMenuItem is IBitmap and MenuItem is Image  -->
-              <Setter Property="Icon" Value="{Binding Icon, Converter={StaticResource AvaloniaThemesDefaultNativeMenuBarIBitmapToImageConverter}}" />
+              <Setter Property="Icon" Value="{Binding Icon, Converter={StaticResource AvaloniaThemesSimpleNativeMenuBarIBitmapToImageConverter}}" />
             </Style>
           </Menu.Styles>
         </Menu>
diff --git a/src/Avalonia.Themes.Default/Controls/NotificationCard.xaml b/src/Avalonia.Themes.Simple/Controls/NotificationCard.xaml
similarity index 100%
rename from src/Avalonia.Themes.Default/Controls/NotificationCard.xaml
rename to src/Avalonia.Themes.Simple/Controls/NotificationCard.xaml
diff --git a/src/Avalonia.Themes.Default/Controls/NumericUpDown.xaml b/src/Avalonia.Themes.Simple/Controls/NumericUpDown.xaml
similarity index 100%
rename from src/Avalonia.Themes.Default/Controls/NumericUpDown.xaml
rename to src/Avalonia.Themes.Simple/Controls/NumericUpDown.xaml
diff --git a/src/Avalonia.Themes.Default/Controls/OverlayPopupHost.xaml b/src/Avalonia.Themes.Simple/Controls/OverlayPopupHost.xaml
similarity index 100%
rename from src/Avalonia.Themes.Default/Controls/OverlayPopupHost.xaml
rename to src/Avalonia.Themes.Simple/Controls/OverlayPopupHost.xaml
diff --git a/src/Avalonia.Themes.Default/Controls/PathIcon.xaml b/src/Avalonia.Themes.Simple/Controls/PathIcon.xaml
similarity index 100%
rename from src/Avalonia.Themes.Default/Controls/PathIcon.xaml
rename to src/Avalonia.Themes.Simple/Controls/PathIcon.xaml
diff --git a/src/Avalonia.Themes.Default/Controls/PopupRoot.xaml b/src/Avalonia.Themes.Simple/Controls/PopupRoot.xaml
similarity index 100%
rename from src/Avalonia.Themes.Default/Controls/PopupRoot.xaml
rename to src/Avalonia.Themes.Simple/Controls/PopupRoot.xaml
diff --git a/src/Avalonia.Themes.Default/Controls/ProgressBar.xaml b/src/Avalonia.Themes.Simple/Controls/ProgressBar.xaml
similarity index 100%
rename from src/Avalonia.Themes.Default/Controls/ProgressBar.xaml
rename to src/Avalonia.Themes.Simple/Controls/ProgressBar.xaml
diff --git a/src/Avalonia.Themes.Default/Controls/RadioButton.xaml b/src/Avalonia.Themes.Simple/Controls/RadioButton.xaml
similarity index 100%
rename from src/Avalonia.Themes.Default/Controls/RadioButton.xaml
rename to src/Avalonia.Themes.Simple/Controls/RadioButton.xaml
diff --git a/src/Avalonia.Themes.Default/Controls/RepeatButton.xaml b/src/Avalonia.Themes.Simple/Controls/RepeatButton.xaml
similarity index 100%
rename from src/Avalonia.Themes.Default/Controls/RepeatButton.xaml
rename to src/Avalonia.Themes.Simple/Controls/RepeatButton.xaml
diff --git a/src/Avalonia.Themes.Default/Controls/RichTextBlock.xaml b/src/Avalonia.Themes.Simple/Controls/RichTextBlock.xaml
similarity index 100%
rename from src/Avalonia.Themes.Default/Controls/RichTextBlock.xaml
rename to src/Avalonia.Themes.Simple/Controls/RichTextBlock.xaml
diff --git a/src/Avalonia.Themes.Default/Controls/ScrollBar.xaml b/src/Avalonia.Themes.Simple/Controls/ScrollBar.xaml
similarity index 100%
rename from src/Avalonia.Themes.Default/Controls/ScrollBar.xaml
rename to src/Avalonia.Themes.Simple/Controls/ScrollBar.xaml
diff --git a/src/Avalonia.Themes.Default/Controls/ScrollViewer.xaml b/src/Avalonia.Themes.Simple/Controls/ScrollViewer.xaml
similarity index 99%
rename from src/Avalonia.Themes.Default/Controls/ScrollViewer.xaml
rename to src/Avalonia.Themes.Simple/Controls/ScrollViewer.xaml
index 83b3330fcf..e11fbb6f15 100644
--- a/src/Avalonia.Themes.Default/Controls/ScrollViewer.xaml
+++ b/src/Avalonia.Themes.Simple/Controls/ScrollViewer.xaml
@@ -56,7 +56,7 @@
     </Setter>
   </ControlTheme>
 
-  <ControlTheme x:Key="DefaultMenuScrollViewer"
+  <ControlTheme x:Key="SimpleMenuScrollViewer"
                 TargetType="ScrollViewer">
     <Setter Property="Background" Value="Transparent" />
     <Setter Property="Template">
diff --git a/src/Avalonia.Themes.Default/Controls/Separator.xaml b/src/Avalonia.Themes.Simple/Controls/Separator.xaml
similarity index 100%
rename from src/Avalonia.Themes.Default/Controls/Separator.xaml
rename to src/Avalonia.Themes.Simple/Controls/Separator.xaml
diff --git a/src/Avalonia.Themes.Simple/Controls/SimpleControls.xaml b/src/Avalonia.Themes.Simple/Controls/SimpleControls.xaml
new file mode 100644
index 0000000000..644c6ed416
--- /dev/null
+++ b/src/Avalonia.Themes.Simple/Controls/SimpleControls.xaml
@@ -0,0 +1,74 @@
+<Styles xmlns="https://github.com/avaloniaui"
+        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
+  <Styles.Resources>
+    <ResourceDictionary>
+      <ResourceDictionary.MergedDictionaries>
+        <ResourceInclude Source="avares://Avalonia.Themes.Simple/Controls/Button.xaml" />
+        <ResourceInclude Source="avares://Avalonia.Themes.Simple/Controls/RadioButton.xaml" />
+        <ResourceInclude Source="avares://Avalonia.Themes.Simple/Controls/Expander.xaml" />
+        <ResourceInclude Source="avares://Avalonia.Themes.Simple/Controls/RepeatButton.xaml" />
+        <ResourceInclude Source="avares://Avalonia.Themes.Simple/Controls/ToggleSwitch.xaml" />
+        <ResourceInclude Source="avares://Avalonia.Themes.Simple/Controls/ButtonSpinner.xaml" />
+        <ResourceInclude Source="avares://Avalonia.Themes.Simple/Controls/ToggleButton.xaml" />
+        <ResourceInclude Source="avares://Avalonia.Themes.Simple/Controls/DropDownButton.xaml" />
+        <ResourceInclude Source="avares://Avalonia.Themes.Simple/Controls/PathIcon.xaml" />
+        <ResourceInclude Source="avares://Avalonia.Themes.Simple/Controls/CheckBox.xaml" />
+        <ResourceInclude Source="avares://Avalonia.Themes.Simple/Controls/ToolTip.xaml" />
+        <ResourceInclude Source="avares://Avalonia.Themes.Simple/Controls/Label.xaml" />
+        <ResourceInclude Source="avares://Avalonia.Themes.Simple/Controls/ComboBoxItem.xaml" />
+        <ResourceInclude Source="avares://Avalonia.Themes.Simple/Controls/ComboBox.xaml" />
+        <ResourceInclude Source="avares://Avalonia.Themes.Simple/Controls/Window.xaml" />
+        <ResourceInclude Source="avares://Avalonia.Themes.Simple/Controls/Carousel.xaml" />
+        <ResourceInclude Source="avares://Avalonia.Themes.Simple/Controls/CaptionButtons.xaml" />
+        <ResourceInclude Source="avares://Avalonia.Themes.Simple/Controls/TitleBar.xaml" />
+        <ResourceInclude Source="avares://Avalonia.Themes.Simple/Controls/TextBox.xaml" />
+        <ResourceInclude Source="avares://Avalonia.Themes.Simple/Controls/AutoCompleteBox.xaml" />
+        <ResourceInclude Source="avares://Avalonia.Themes.Simple/Controls/DataValidationErrors.xaml" />
+        <ResourceInclude Source="avares://Avalonia.Themes.Simple/Controls/ContentControl.xaml" />
+        <ResourceInclude Source="avares://Avalonia.Themes.Simple/Controls/FlyoutPresenter.xaml" />
+        <ResourceInclude Source="avares://Avalonia.Themes.Simple/Controls/MenuFlyoutPresenter.xaml" />
+        <ResourceInclude Source="avares://Avalonia.Themes.Simple/Controls/GridSplitter.xaml" />
+        <ResourceInclude Source="avares://Avalonia.Themes.Simple/Controls/ItemsControl.xaml" />
+        <ResourceInclude Source="avares://Avalonia.Themes.Simple/Controls/ListBoxItem.xaml" />
+        <ResourceInclude Source="avares://Avalonia.Themes.Simple/Controls/ListBox.xaml" />
+        <ResourceInclude Source="avares://Avalonia.Themes.Simple/Controls/ScrollBar.xaml" />
+        <ResourceInclude Source="avares://Avalonia.Themes.Simple/Controls/ScrollViewer.xaml" />
+        <ResourceInclude Source="avares://Avalonia.Themes.Simple/Controls/TabStrip.xaml" />
+        <ResourceInclude Source="avares://Avalonia.Themes.Simple/Controls/TabStripItem.xaml" />
+        <ResourceInclude Source="avares://Avalonia.Themes.Simple/Controls/TabControl.xaml" />
+        <ResourceInclude Source="avares://Avalonia.Themes.Simple/Controls/TabItem.xaml" />
+        <ResourceInclude Source="avares://Avalonia.Themes.Simple/Controls/PopupRoot.xaml" />
+        <ResourceInclude Source="avares://Avalonia.Themes.Simple/Controls/OverlayPopupHost.xaml" />
+        <ResourceInclude Source="avares://Avalonia.Themes.Simple/Controls/WindowNotificationManager.xaml" />
+        <ResourceInclude Source="avares://Avalonia.Themes.Simple/Controls/EmbeddableControlRoot.xaml" />
+        <ResourceInclude Source="avares://Avalonia.Themes.Simple/Controls/TransitioningContentControl.xaml" />
+        <ResourceInclude Source="avares://Avalonia.Themes.Simple/Controls/TreeView.xaml" />
+        <ResourceInclude Source="avares://Avalonia.Themes.Simple/Controls/TreeViewItem.xaml" />
+        <ResourceInclude Source="avares://Avalonia.Themes.Simple/Controls/ProgressBar.xaml" />
+        <ResourceInclude Source="avares://Avalonia.Themes.Simple/Controls/Separator.xaml" />
+        <ResourceInclude Source="avares://Avalonia.Themes.Simple/Controls/Menu.xaml" />
+        <ResourceInclude Source="avares://Avalonia.Themes.Simple/Controls/MenuItem.xaml" />
+        <ResourceInclude Source="avares://Avalonia.Themes.Simple/Controls/ContextMenu.xaml" />
+        <ResourceInclude Source="avares://Avalonia.Themes.Simple/Controls/CalendarButton.xaml" />
+        <ResourceInclude Source="avares://Avalonia.Themes.Simple/Controls/CalendarDayButton.xaml" />
+        <ResourceInclude Source="avares://Avalonia.Themes.Simple/Controls/CalendarItem.xaml" />
+        <ResourceInclude Source="avares://Avalonia.Themes.Simple/Controls/Calendar.xaml" />
+        <ResourceInclude Source="avares://Avalonia.Themes.Simple/Controls/CalendarDatePicker.xaml" />
+        <ResourceInclude Source="avares://Avalonia.Themes.Simple/Controls/Slider.xaml" />
+        <ResourceInclude Source="avares://Avalonia.Themes.Simple/Controls/NotificationCard.xaml" />
+        <ResourceInclude Source="avares://Avalonia.Themes.Simple/Controls/NativeMenuBar.xaml" />
+        <ResourceInclude Source="avares://Avalonia.Themes.Simple/Controls/NumericUpDown.xaml" />
+        <ResourceInclude Source="avares://Avalonia.Themes.Simple/Controls/DateTimePickerShared.xaml" />
+        <ResourceInclude Source="avares://Avalonia.Themes.Simple/Controls/DatePicker.xaml" />
+        <ResourceInclude Source="avares://Avalonia.Themes.Simple/Controls/TimePicker.xaml" />
+        <ResourceInclude Source="avares://Avalonia.Themes.Simple/Controls/SplitView.xaml" />
+        <ResourceInclude Source="avares://Avalonia.Themes.Simple/Controls/ManagedFileChooser.xaml" />
+        <ResourceInclude Source="avares://Avalonia.Themes.Simple/Controls/SplitButton.xaml" />
+        <ResourceInclude Source="avares://Avalonia.Themes.Simple/Controls/RichTextBlock.xaml" />
+      </ResourceDictionary.MergedDictionaries>
+    </ResourceDictionary>
+  </Styles.Resources>
+
+  <StyleInclude Source="avares://Avalonia.Themes.Simple/Controls/FocusAdorner.xaml" />
+  <StyleInclude Source="avares://Avalonia.Themes.Simple/Controls/UserControl.xaml" />
+</Styles>
diff --git a/src/Avalonia.Themes.Default/Controls/Slider.xaml b/src/Avalonia.Themes.Simple/Controls/Slider.xaml
similarity index 100%
rename from src/Avalonia.Themes.Default/Controls/Slider.xaml
rename to src/Avalonia.Themes.Simple/Controls/Slider.xaml
diff --git a/src/Avalonia.Themes.Default/Controls/SplitButton.xaml b/src/Avalonia.Themes.Simple/Controls/SplitButton.xaml
similarity index 98%
rename from src/Avalonia.Themes.Default/Controls/SplitButton.xaml
rename to src/Avalonia.Themes.Simple/Controls/SplitButton.xaml
index aa71d0e7c7..f0d22aac97 100644
--- a/src/Avalonia.Themes.Default/Controls/SplitButton.xaml
+++ b/src/Avalonia.Themes.Simple/Controls/SplitButton.xaml
@@ -3,7 +3,7 @@
                     x:CompileBindings="True"
                     xmlns:converters="using:Avalonia.Controls.Converters">
 
-  <!-- This style is heavily based on the Default v1 style.
+  <!-- This style is heavily based on the Fluent v1 style.
        The base resources are switched out along with a few minor changes such as Padding, CornerRadius. -->
 
   <Design.PreviewWith>
@@ -58,7 +58,7 @@
   <SolidColorBrush x:Key="SplitButtonBorderBrushCheckedDisabled" Color="{DynamicResource ThemeControlMidColor}"
                    Opacity="{DynamicResource ThemeDisabledOpacity}" />
 
-  <ControlTheme x:Key="DefaultSplitButtonComponent" TargetType="Button">
+  <ControlTheme x:Key="SimpleSplitButtonComponent" TargetType="Button">
     <Setter Property="Template">
       <ControlTemplate>
         <ContentPresenter x:Name="PART_ContentPresenter"
@@ -156,7 +156,7 @@
 
           <Button x:Name="PART_PrimaryButton"
                   Grid.Column="0"
-                  Theme="{StaticResource DefaultSplitButtonComponent}"
+                  Theme="{StaticResource SimpleSplitButtonComponent}"
                   MinWidth="{DynamicResource SplitButtonPrimaryButtonSize}"
                   Foreground="{TemplateBinding Foreground}"
                   Background="{TemplateBinding Background}"
@@ -187,7 +187,7 @@
 
           <Button x:Name="PART_SecondaryButton"
                   Grid.Column="2"
-                  Theme="{StaticResource DefaultSplitButtonComponent}"
+                  Theme="{StaticResource SimpleSplitButtonComponent}"
                   MinWidth="{DynamicResource SplitButtonSecondaryButtonSize}"
                   BorderBrush="{TemplateBinding BorderBrush}"
                   Foreground="{TemplateBinding Foreground}"
diff --git a/src/Avalonia.Themes.Default/Controls/SplitView.xaml b/src/Avalonia.Themes.Simple/Controls/SplitView.xaml
similarity index 100%
rename from src/Avalonia.Themes.Default/Controls/SplitView.xaml
rename to src/Avalonia.Themes.Simple/Controls/SplitView.xaml
diff --git a/src/Avalonia.Themes.Default/Controls/TabControl.xaml b/src/Avalonia.Themes.Simple/Controls/TabControl.xaml
similarity index 100%
rename from src/Avalonia.Themes.Default/Controls/TabControl.xaml
rename to src/Avalonia.Themes.Simple/Controls/TabControl.xaml
diff --git a/src/Avalonia.Themes.Default/Controls/TabItem.xaml b/src/Avalonia.Themes.Simple/Controls/TabItem.xaml
similarity index 100%
rename from src/Avalonia.Themes.Default/Controls/TabItem.xaml
rename to src/Avalonia.Themes.Simple/Controls/TabItem.xaml
diff --git a/src/Avalonia.Themes.Default/Controls/TabStrip.xaml b/src/Avalonia.Themes.Simple/Controls/TabStrip.xaml
similarity index 100%
rename from src/Avalonia.Themes.Default/Controls/TabStrip.xaml
rename to src/Avalonia.Themes.Simple/Controls/TabStrip.xaml
diff --git a/src/Avalonia.Themes.Default/Controls/TabStripItem.xaml b/src/Avalonia.Themes.Simple/Controls/TabStripItem.xaml
similarity index 100%
rename from src/Avalonia.Themes.Default/Controls/TabStripItem.xaml
rename to src/Avalonia.Themes.Simple/Controls/TabStripItem.xaml
diff --git a/src/Avalonia.Themes.Default/Controls/TextBox.xaml b/src/Avalonia.Themes.Simple/Controls/TextBox.xaml
similarity index 96%
rename from src/Avalonia.Themes.Default/Controls/TextBox.xaml
rename to src/Avalonia.Themes.Simple/Controls/TextBox.xaml
index 3cc8bc5421..5fa6412688 100644
--- a/src/Avalonia.Themes.Default/Controls/TextBox.xaml
+++ b/src/Avalonia.Themes.Simple/Controls/TextBox.xaml
@@ -4,7 +4,7 @@
   <StreamGeometry x:Key="PasswordBoxRevealButtonData">m10.051 7.0032c2.215 0 4.0105 1.7901 4.0105 3.9984s-1.7956 3.9984-4.0105 3.9984c-2.215 0-4.0105-1.7901-4.0105-3.9984s1.7956-3.9984 4.0105-3.9984zm0 1.4994c-1.3844 0-2.5066 1.1188-2.5066 2.499s1.1222 2.499 2.5066 2.499 2.5066-1.1188 2.5066-2.499-1.1222-2.499-2.5066-2.499zm0-5.0026c4.6257 0 8.6188 3.1487 9.7267 7.5613 0.10085 0.40165-0.14399 0.80877-0.54686 0.90931-0.40288 0.10054-0.81122-0.14355-0.91208-0.54521-0.94136-3.7492-4.3361-6.4261-8.2678-6.4261-3.9334 0-7.3292 2.6792-8.2689 6.4306-0.10063 0.40171-0.50884 0.64603-0.91177 0.54571s-0.648-0.5073-0.54737-0.90901c1.106-4.4152 5.1003-7.5667 9.728-7.5667z</StreamGeometry>
   <StreamGeometry x:Key="PasswordBoxHideButtonData">m0.21967 0.21965c-0.26627 0.26627-0.29047 0.68293-0.07262 0.97654l0.07262 0.08412 4.0346 4.0346c-1.922 1.3495-3.3585 3.365-3.9554 5.7495-0.10058 0.4018 0.14362 0.8091 0.54543 0.9097 0.40182 0.1005 0.80909-0.1436 0.90968-0.5455 0.52947-2.1151 1.8371-3.8891 3.5802-5.0341l1.8096 1.8098c-0.70751 0.7215-1.1438 1.71-1.1438 2.8003 0 2.2092 1.7909 4 4 4 1.0904 0 2.0788-0.4363 2.8004-1.1438l5.9193 5.9195c0.2929 0.2929 0.7677 0.2929 1.0606 0 0.2663-0.2662 0.2905-0.6829 0.0726-0.9765l-0.0726-0.0841-6.1135-6.1142 0.0012-0.0015-1.2001-1.1979-2.8699-2.8693 2e-3 -8e-4 -2.8812-2.8782 0.0012-0.0018-1.1333-1.1305-4.3064-4.3058c-0.29289-0.29289-0.76777-0.29289-1.0607 0zm7.9844 9.0458 3.5351 3.5351c-0.45 0.4358-1.0633 0.704-1.7392 0.704-1.3807 0-2.5-1.1193-2.5-2.5 0-0.6759 0.26824-1.2892 0.7041-1.7391zm1.7959-5.7655c-1.0003 0-1.9709 0.14807-2.8889 0.425l1.237 1.2362c0.5358-0.10587 1.0883-0.16119 1.6519-0.16119 3.9231 0 7.3099 2.6803 8.2471 6.4332 0.1004 0.4018 0.5075 0.6462 0.9094 0.5459 0.4019-0.1004 0.6463-0.5075 0.5459-0.9094-1.103-4.417-5.0869-7.5697-9.7024-7.5697zm0.1947 3.5093 3.8013 3.8007c-0.1018-2.0569-1.7488-3.7024-3.8013-3.8007z</StreamGeometry>
 
-  <MenuFlyout x:Key="DefaultTextBoxContextFlyout" Placement="Bottom">
+  <MenuFlyout x:Key="SimpleTextBoxContextFlyout" Placement="Bottom">
     <MenuItem x:Name="TextBoxContextFlyoutCutItem" Header="Cut" Command="{Binding $parent[TextBox].Cut}"
               IsEnabled="{Binding $parent[TextBox].CanCut}" InputGesture="{x:Static TextBox.CutGesture}" />
     <MenuItem x:Name="TextBoxContextFlyoutCopyItem" Header="Copy" Command="{Binding $parent[TextBox].Copy}"
@@ -13,7 +13,7 @@
               IsEnabled="{Binding $parent[TextBox].CanPaste}" InputGesture="{x:Static TextBox.PasteGesture}" />
   </MenuFlyout>
 
-  <ContextMenu x:Key="DefaultTextBoxContextMenu" x:Name="TextBoxContextMenu">
+  <ContextMenu x:Key="SimpleTextBoxContextMenu" x:Name="TextBoxContextMenu">
     <MenuItem x:Name="TextBoxContextMenuCutItem" Header="Cut" Command="{Binding $parent[TextBox].Cut}"
               IsEnabled="{Binding $parent[TextBox].CanCut}" InputGesture="{x:Static TextBox.CutGesture}" />
     <MenuItem x:Name="TextBoxContextMenuCopyItem" Header="Copy" Command="{Binding $parent[TextBox].Copy}"
@@ -22,7 +22,7 @@
               IsEnabled="{Binding $parent[TextBox].CanPaste}" InputGesture="{x:Static TextBox.PasteGesture}" />
   </ContextMenu>
 
-  <ControlTheme x:Key="DefaultTextBoxClearButtonTheme"
+  <ControlTheme x:Key="SimpleTextBoxClearButtonTheme"
                 BasedOn="{StaticResource {x:Type Button}}"
                 TargetType="Button">
     <Setter Property="Cursor" Value="Arrow" />
@@ -46,7 +46,7 @@
     </Setter>
   </ControlTheme>
 
-  <ControlTheme x:Key="DefaultPasswordBoxRevealButtonTheme"
+  <ControlTheme x:Key="SimplePasswordBoxRevealButtonTheme"
                 BasedOn="{StaticResource {x:Type Button}}"
                 TargetType="ToggleButton">
     <Setter Property="Cursor" Value="Arrow" />
@@ -96,7 +96,7 @@
     <Setter Property="SelectionBrush" Value="{DynamicResource HighlightBrush}" />
     <Setter Property="SelectionForegroundBrush" Value="{DynamicResource HighlightForegroundBrush}" />
     <Setter Property="Padding" Value="4" />
-    <Setter Property="ContextFlyout" Value="{StaticResource DefaultTextBoxContextFlyout}" />
+    <Setter Property="ContextFlyout" Value="{StaticResource SimpleTextBoxContextFlyout}" />
     <Setter Property="ScrollViewer.IsScrollChainingEnabled" Value="True" />
     <Setter Property="Template">
       <ControlTemplate>
@@ -192,7 +192,7 @@
         <Template>
           <Button Command="{Binding $parent[TextBox].Clear}"
                   Focusable="False"
-                  Theme="{StaticResource DefaultTextBoxClearButtonTheme}" />
+                  Theme="{StaticResource SimpleTextBoxClearButtonTheme}" />
         </Template>
       </Setter>
     </Style>
@@ -212,7 +212,7 @@
             <ToggleButton Background="Transparent"
                           Focusable="False"
                           IsChecked="{Binding $parent[TextBox].RevealPassword, Mode=TwoWay}"
-                          Theme="{StaticResource DefaultPasswordBoxRevealButtonTheme}" />
+                          Theme="{StaticResource SimplePasswordBoxRevealButtonTheme}" />
           </Panel>
         </Template>
       </Setter>
diff --git a/src/Avalonia.Themes.Default/Controls/TimePicker.xaml b/src/Avalonia.Themes.Simple/Controls/TimePicker.xaml
similarity index 94%
rename from src/Avalonia.Themes.Default/Controls/TimePicker.xaml
rename to src/Avalonia.Themes.Simple/Controls/TimePicker.xaml
index b0ffc97e68..c49b3aec4e 100644
--- a/src/Avalonia.Themes.Default/Controls/TimePicker.xaml
+++ b/src/Avalonia.Themes.Simple/Controls/TimePicker.xaml
@@ -41,7 +41,7 @@
   <Thickness x:Key="TimePickerFlyoutPresenterItemPadding">0,3,0,6</Thickness>
   <Thickness x:Key="TimePickerHostPadding">0,3,0,6</Thickness>
 
-  <ControlTheme x:Key="DefaultTimePickerFlyoutButton"
+  <ControlTheme x:Key="SimpleTimePickerFlyoutButton"
                 TargetType="Button">
     <Setter Property="RenderTransform" Value="none" />
     <Setter Property="Template">
@@ -114,7 +114,7 @@
                     CornerRadius="{TemplateBinding CornerRadius}"
                     Foreground="{TemplateBinding Foreground}"
                     IsEnabled="{TemplateBinding IsEnabled}"
-                    Theme="{StaticResource DefaultTimePickerFlyoutButton}">
+                    Theme="{StaticResource SimpleTimePickerFlyoutButton}">
 
               <Grid Name="FlyoutButtonContentGrid">
                 <!--  Ignore col defs here, set in code  -->
@@ -226,9 +226,9 @@
                                        ShouldLoop="True" />
                 </ScrollViewer>
                 <RepeatButton Name="HourUpButton"
-                              Theme="{StaticResource DefaultDateTimePickerUpButton}" />
+                              Theme="{StaticResource SimpleDateTimePickerUpButton}" />
                 <RepeatButton Name="HourDownButton"
-                              Theme="{StaticResource DefaultDateTimePickerDownButton}" />
+                              Theme="{StaticResource SimpleDateTimePickerDownButton}" />
               </Panel>
 
               <Panel Name="MinuteHost"
@@ -241,9 +241,9 @@
                                        ShouldLoop="True" />
                 </ScrollViewer>
                 <RepeatButton Name="MinuteUpButton"
-                              Theme="{StaticResource DefaultDateTimePickerUpButton}" />
+                              Theme="{StaticResource SimpleDateTimePickerUpButton}" />
                 <RepeatButton Name="MinuteDownButton"
-                              Theme="{StaticResource DefaultDateTimePickerDownButton}" />
+                              Theme="{StaticResource SimpleDateTimePickerDownButton}" />
               </Panel>
 
               <Panel Name="PeriodHost"
@@ -256,9 +256,9 @@
                                        ShouldLoop="False" />
                 </ScrollViewer>
                 <RepeatButton Name="PeriodUpButton"
-                              Theme="{StaticResource DefaultDateTimePickerUpButton}" />
+                              Theme="{StaticResource SimpleDateTimePickerUpButton}" />
                 <RepeatButton Name="PeriodDownButton"
-                              Theme="{StaticResource DefaultDateTimePickerDownButton}" />
+                              Theme="{StaticResource SimpleDateTimePickerDownButton}" />
               </Panel>
 
               <Rectangle x:Name="HighlightRect"
@@ -296,7 +296,7 @@
                       Height="{DynamicResource TimePickerFlyoutPresenterAcceptDismissHostGridHeight}"
                       HorizontalAlignment="Stretch"
                       VerticalAlignment="Stretch"
-                      Theme="{StaticResource DefaultDateTimePickerButton}">
+                      Theme="{StaticResource SimpleDateTimePickerButton}">
                 <Path Data="M0.5,8.5 5,13.5 15.5,3"
                       Stroke="{Binding $parent[Button].Foreground}"
                       StrokeLineCap="Round"
@@ -308,7 +308,7 @@
                       HorizontalAlignment="Stretch"
                       VerticalAlignment="Stretch"
                       FontSize="16"
-                      Theme="{StaticResource DefaultDateTimePickerButton}">
+                      Theme="{StaticResource SimpleDateTimePickerButton}">
                 <Path Data="M2,2 14,14 M2,14 14 2"
                       Stroke="{Binding $parent[Button].Foreground}"
                       StrokeLineCap="Round"
diff --git a/src/Avalonia.Themes.Default/Controls/TitleBar.xaml b/src/Avalonia.Themes.Simple/Controls/TitleBar.xaml
similarity index 100%
rename from src/Avalonia.Themes.Default/Controls/TitleBar.xaml
rename to src/Avalonia.Themes.Simple/Controls/TitleBar.xaml
diff --git a/src/Avalonia.Themes.Default/Controls/ToggleButton.xaml b/src/Avalonia.Themes.Simple/Controls/ToggleButton.xaml
similarity index 100%
rename from src/Avalonia.Themes.Default/Controls/ToggleButton.xaml
rename to src/Avalonia.Themes.Simple/Controls/ToggleButton.xaml
diff --git a/src/Avalonia.Themes.Default/Controls/ToggleSwitch.xaml b/src/Avalonia.Themes.Simple/Controls/ToggleSwitch.xaml
similarity index 100%
rename from src/Avalonia.Themes.Default/Controls/ToggleSwitch.xaml
rename to src/Avalonia.Themes.Simple/Controls/ToggleSwitch.xaml
diff --git a/src/Avalonia.Themes.Default/Controls/ToolTip.xaml b/src/Avalonia.Themes.Simple/Controls/ToolTip.xaml
similarity index 100%
rename from src/Avalonia.Themes.Default/Controls/ToolTip.xaml
rename to src/Avalonia.Themes.Simple/Controls/ToolTip.xaml
diff --git a/src/Avalonia.Themes.Default/Controls/TransitioningContentControl.xaml b/src/Avalonia.Themes.Simple/Controls/TransitioningContentControl.xaml
similarity index 100%
rename from src/Avalonia.Themes.Default/Controls/TransitioningContentControl.xaml
rename to src/Avalonia.Themes.Simple/Controls/TransitioningContentControl.xaml
diff --git a/src/Avalonia.Themes.Default/Controls/TreeView.xaml b/src/Avalonia.Themes.Simple/Controls/TreeView.xaml
similarity index 100%
rename from src/Avalonia.Themes.Default/Controls/TreeView.xaml
rename to src/Avalonia.Themes.Simple/Controls/TreeView.xaml
diff --git a/src/Avalonia.Themes.Default/Controls/TreeViewItem.xaml b/src/Avalonia.Themes.Simple/Controls/TreeViewItem.xaml
similarity index 96%
rename from src/Avalonia.Themes.Default/Controls/TreeViewItem.xaml
rename to src/Avalonia.Themes.Simple/Controls/TreeViewItem.xaml
index 7baf0ef2a6..8b3452244c 100644
--- a/src/Avalonia.Themes.Default/Controls/TreeViewItem.xaml
+++ b/src/Avalonia.Themes.Simple/Controls/TreeViewItem.xaml
@@ -5,7 +5,7 @@
                                         Indent="16"
                                         Left="True" />
 
-  <ControlTheme x:Key="DefaultTreeViewItemToggleButtonTheme"
+  <ControlTheme x:Key="SimpleTreeViewItemToggleButtonTheme"
                 TargetType="ToggleButton">
     <Setter Property="Template">
       <ControlTemplate>
@@ -52,7 +52,7 @@
                             Focusable="False"
                             IsChecked="{TemplateBinding IsExpanded,
                                                         Mode=TwoWay}"
-                            Theme="{StaticResource DefaultTreeViewItemToggleButtonTheme}" />
+                            Theme="{StaticResource SimpleTreeViewItemToggleButtonTheme}" />
               <ContentPresenter Name="PART_HeaderPresenter"
                                 Grid.Column="1"
                                 Padding="{TemplateBinding Padding}"
diff --git a/src/Avalonia.Themes.Default/Controls/UserControl.xaml b/src/Avalonia.Themes.Simple/Controls/UserControl.xaml
similarity index 90%
rename from src/Avalonia.Themes.Default/Controls/UserControl.xaml
rename to src/Avalonia.Themes.Simple/Controls/UserControl.xaml
index 56248f8c5f..3316b0298c 100644
--- a/src/Avalonia.Themes.Default/Controls/UserControl.xaml
+++ b/src/Avalonia.Themes.Simple/Controls/UserControl.xaml
@@ -2,7 +2,7 @@
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        Selector=":is(UserControl)">
   <Style.Resources>
-    <ControlTheme x:Key="DefaultUserControl"
+    <ControlTheme x:Key="SimpleUserControl"
                   TargetType="UserControl">
       <Setter Property="Template">
         <ControlTemplate>
@@ -21,5 +21,5 @@
     </ControlTheme>
   </Style.Resources>
 
-  <Setter Property="Theme" Value="{StaticResource DefaultUserControl}" />
+  <Setter Property="Theme" Value="{StaticResource SimpleUserControl}" />
 </Style>
diff --git a/src/Avalonia.Themes.Default/Controls/Window.xaml b/src/Avalonia.Themes.Simple/Controls/Window.xaml
similarity index 100%
rename from src/Avalonia.Themes.Default/Controls/Window.xaml
rename to src/Avalonia.Themes.Simple/Controls/Window.xaml
diff --git a/src/Avalonia.Themes.Default/Controls/WindowNotificationManager.xaml b/src/Avalonia.Themes.Simple/Controls/WindowNotificationManager.xaml
similarity index 100%
rename from src/Avalonia.Themes.Default/Controls/WindowNotificationManager.xaml
rename to src/Avalonia.Themes.Simple/Controls/WindowNotificationManager.xaml
diff --git a/src/Avalonia.Themes.Default/IBitmapToImageConverter.cs b/src/Avalonia.Themes.Simple/IBitmapToImageConverter.cs
similarity index 95%
rename from src/Avalonia.Themes.Default/IBitmapToImageConverter.cs
rename to src/Avalonia.Themes.Simple/IBitmapToImageConverter.cs
index 9b7fcecf45..fade026b51 100644
--- a/src/Avalonia.Themes.Default/IBitmapToImageConverter.cs
+++ b/src/Avalonia.Themes.Simple/IBitmapToImageConverter.cs
@@ -8,7 +8,7 @@ using Avalonia.Controls;
 using Avalonia.Data.Converters;
 using Avalonia.Media.Imaging;
 
-namespace Avalonia.Themes.Default
+namespace Avalonia.Themes.Simple
 {
     internal class IBitmapToImageConverter : IValueConverter
     {
diff --git a/src/Avalonia.Themes.Default/InverseBooleanValueConverter.cs b/src/Avalonia.Themes.Simple/InverseBooleanValueConverter.cs
similarity index 94%
rename from src/Avalonia.Themes.Default/InverseBooleanValueConverter.cs
rename to src/Avalonia.Themes.Simple/InverseBooleanValueConverter.cs
index 7befc81b8e..15cc5b4a80 100644
--- a/src/Avalonia.Themes.Default/InverseBooleanValueConverter.cs
+++ b/src/Avalonia.Themes.Simple/InverseBooleanValueConverter.cs
@@ -2,7 +2,7 @@ using System;
 using System.Globalization;
 using Avalonia.Data.Converters;
 
-namespace Avalonia.Themes.Default
+namespace Avalonia.Themes.Simple
 {
     class InverseBooleanValueConverter : IValueConverter
     {
diff --git a/src/Avalonia.Themes.Simple/Properties/AssemblyInfo.cs b/src/Avalonia.Themes.Simple/Properties/AssemblyInfo.cs
new file mode 100644
index 0000000000..f00510816a
--- /dev/null
+++ b/src/Avalonia.Themes.Simple/Properties/AssemblyInfo.cs
@@ -0,0 +1,3 @@
+using Avalonia.Metadata;
+
+[assembly: XmlnsDefinition("https://github.com/avaloniaui", "Avalonia.Themes.Simple")]
diff --git a/src/Avalonia.Themes.Default/SimpleTheme.cs b/src/Avalonia.Themes.Simple/SimpleTheme.cs
similarity index 89%
rename from src/Avalonia.Themes.Default/SimpleTheme.cs
rename to src/Avalonia.Themes.Simple/SimpleTheme.cs
index 98e35355c8..f225cb4c4d 100644
--- a/src/Avalonia.Themes.Default/SimpleTheme.cs
+++ b/src/Avalonia.Themes.Simple/SimpleTheme.cs
@@ -6,7 +6,7 @@ using Avalonia.Markup.Xaml.Styling;
 using Avalonia.Styling;
 #nullable enable
 
-namespace Avalonia.Themes.Default
+namespace Avalonia.Themes.Simple
 {
     public class SimpleTheme : AvaloniaObject, IStyle, IResourceProvider
     {
@@ -23,9 +23,9 @@ namespace Avalonia.Themes.Default
         /// Initializes a new instance of the <see cref="SimpleTheme"/> class.
         /// </summary>
         /// <param name="baseUri">The base URL for the XAML context.</param>
-        public SimpleTheme(Uri baseUri)
+        public SimpleTheme(Uri? baseUri = null)
         {
-            _baseUri = baseUri;
+            _baseUri = baseUri ?? new Uri("avares://Avalonia.Themes.Simple/");
             InitStyles(_baseUri);
         }
 
@@ -138,18 +138,18 @@ namespace Avalonia.Themes.Default
             {
                 new StyleInclude(baseUri)
                 {
-                    Source = new Uri("avares://Avalonia.Themes.Default/DefaultTheme.xaml")
+                    Source = new Uri("avares://Avalonia.Themes.Simple/Controls/SimpleControls.xaml")
                 },
                 new StyleInclude(baseUri)
                 {
-                    Source = new Uri("avares://Avalonia.Themes.Default/Accents/Base.xaml")
+                    Source = new Uri("avares://Avalonia.Themes.Simple/Accents/Base.xaml")
                 }
             };
             _simpleLight = new Styles
             {
                 new StyleInclude(baseUri)
                 {
-                    Source = new Uri("avares://Avalonia.Themes.Default/Accents/BaseLight.xaml")
+                    Source = new Uri("avares://Avalonia.Themes.Simple/Accents/BaseLight.xaml")
                 }
             };
 
@@ -157,7 +157,7 @@ namespace Avalonia.Themes.Default
             {
                 new StyleInclude(baseUri)
                 {
-                    Source = new Uri("avares://Avalonia.Themes.Default/Accents/BaseDark.xaml")
+                    Source = new Uri("avares://Avalonia.Themes.Simple/Accents/BaseDark.xaml")
                 }
             };
         }
diff --git a/src/Avalonia.Themes.Default/SimpleThemeMode.cs b/src/Avalonia.Themes.Simple/SimpleThemeMode.cs
similarity index 67%
rename from src/Avalonia.Themes.Default/SimpleThemeMode.cs
rename to src/Avalonia.Themes.Simple/SimpleThemeMode.cs
index be33466327..683c751f10 100644
--- a/src/Avalonia.Themes.Default/SimpleThemeMode.cs
+++ b/src/Avalonia.Themes.Simple/SimpleThemeMode.cs
@@ -1,4 +1,4 @@
-namespace Avalonia.Themes.Default
+namespace Avalonia.Themes.Simple
 {
     public enum SimpleThemeMode
     {
diff --git a/src/tools/Avalonia.Designer.HostApp/Avalonia.Designer.HostApp.csproj b/src/tools/Avalonia.Designer.HostApp/Avalonia.Designer.HostApp.csproj
index 1cf68c1605..f509bb21ba 100644
--- a/src/tools/Avalonia.Designer.HostApp/Avalonia.Designer.HostApp.csproj
+++ b/src/tools/Avalonia.Designer.HostApp/Avalonia.Designer.HostApp.csproj
@@ -10,7 +10,7 @@
     <ProjectReference Include="..\..\Avalonia.Base\Avalonia.Base.csproj" />
     <ProjectReference Include="..\..\Avalonia.Controls\Avalonia.Controls.csproj" />
     <ProjectReference Include="..\..\Avalonia.Diagnostics\Avalonia.Diagnostics.csproj" />
-    <ProjectReference Include="..\..\Avalonia.Themes.Default\Avalonia.Themes.Default.csproj" />
+    <ProjectReference Include="..\..\Avalonia.Themes.Simple\Avalonia.Themes.Simple.csproj" />
   </ItemGroup>
   <Import Project="..\..\..\src\Markup\Avalonia.Markup.Xaml.Loader\IncludeXamlIlSre.props" />
   <ItemGroup>
diff --git a/tests/Avalonia.Base.UnitTests/Utilities/UriExtensionsTests.cs b/tests/Avalonia.Base.UnitTests/Utilities/UriExtensionsTests.cs
index 5c3ac6adeb..4a879c8ced 100644
--- a/tests/Avalonia.Base.UnitTests/Utilities/UriExtensionsTests.cs
+++ b/tests/Avalonia.Base.UnitTests/Utilities/UriExtensionsTests.cs
@@ -10,9 +10,9 @@ public class UriExtensionsTests
     public void Assembly_Name_From_Query_Parsed()
     {
         const string key = "assembly";
-        const string value = "Avalonia.Themes.Default";
+        const string value = "Avalonia.Themes.Simple";
 
-        var uri = new Uri($"resm:Avalonia.Themes.Default.Accents.BaseLight.xaml?{key}={value}");
+        var uri = new Uri($"resm:Avalonia.Themes.Simple.Accents.BaseLight.xaml?{key}={value}");
         var name = uri.GetAssemblyNameFromQuery();
 
         Assert.Equal(value, name);
@@ -21,7 +21,7 @@ public class UriExtensionsTests
     [Fact]
     public void Assembly_Name_From_Empty_Query_Not_Parsed()
     {
-        var uri = new Uri("resm:Avalonia.Themes.Default.Accents.BaseLight.xaml");
+        var uri = new Uri("resm:Avalonia.Themes.Simple.Accents.BaseLight.xaml");
         var name = uri.GetAssemblyNameFromQuery();
 
         Assert.Equal(string.Empty, name);
diff --git a/tests/Avalonia.Benchmarks/Avalonia.Benchmarks.csproj b/tests/Avalonia.Benchmarks/Avalonia.Benchmarks.csproj
index 5d17808e0c..3f4978f544 100644
--- a/tests/Avalonia.Benchmarks/Avalonia.Benchmarks.csproj
+++ b/tests/Avalonia.Benchmarks/Avalonia.Benchmarks.csproj
@@ -9,7 +9,7 @@
     <ProjectReference Include="..\..\src\Avalonia.Base\Avalonia.Base.csproj" />
     <ProjectReference Include="..\..\src\Avalonia.Controls\Avalonia.Controls.csproj" />
     <ProjectReference Include="..\..\src\Avalonia.Themes.Fluent\Avalonia.Themes.Fluent.csproj" />
-    <ProjectReference Include="..\..\src\Avalonia.Themes.Default\Avalonia.Themes.Default.csproj" />
+    <ProjectReference Include="..\..\src\Avalonia.Themes.Simple\Avalonia.Themes.Simple.csproj" />
     <ProjectReference Include="..\Avalonia.UnitTests\Avalonia.UnitTests.csproj" />
   </ItemGroup>
   <ItemGroup>
diff --git a/tests/Avalonia.Benchmarks/Themes/ThemeBenchmark.cs b/tests/Avalonia.Benchmarks/Themes/ThemeBenchmark.cs
index 9a5b49790d..c64931a6ef 100644
--- a/tests/Avalonia.Benchmarks/Themes/ThemeBenchmark.cs
+++ b/tests/Avalonia.Benchmarks/Themes/ThemeBenchmark.cs
@@ -37,8 +37,8 @@ namespace Avalonia.Benchmarks.Themes
         }
 
         [Benchmark]
-        [Arguments("avares://Avalonia.Themes.Default/Accents/BaseLight.xaml")]
-        [Arguments("avares://Avalonia.Themes.Default/Accents/BaseDark.xaml")]
+        [Arguments("avares://Avalonia.Themes.Simple/Accents/BaseLight.xaml")]
+        [Arguments("avares://Avalonia.Themes.Simple/Accents/BaseDark.xaml")]
         public bool InitDefaultTheme(string themeUri)
         {
             UnitTestApplication.Current.Styles[0] = new Styles
@@ -49,7 +49,7 @@ namespace Avalonia.Benchmarks.Themes
                 },
                 new StyleInclude(new Uri("resm:Styles?assembly=Avalonia.Benchmarks"))
                 {
-                    Source = new Uri("avares://Avalonia.Themes.Default/DefaultTheme.xaml")
+                    Source = new Uri("avares://Avalonia.Themes.Simple/DefaultTheme.xaml")
                 }
             };
             return ((IResourceHost)UnitTestApplication.Current).TryGetResource("ThemeAccentColor", out _);
diff --git a/tests/Avalonia.DesignerSupport.TestApp/App.xaml b/tests/Avalonia.DesignerSupport.TestApp/App.xaml
index 5a33ffff80..803cae09c8 100644
--- a/tests/Avalonia.DesignerSupport.TestApp/App.xaml
+++ b/tests/Avalonia.DesignerSupport.TestApp/App.xaml
@@ -3,8 +3,8 @@
     xmlns="https://github.com/avaloniaui"
     xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
     <Application.Styles>
-        <StyleInclude Source="avares://Avalonia.Themes.Default/DefaultTheme.xaml" />
-        <StyleInclude Source="avares://Avalonia.Themes.Default/Accents/Base.xaml" />
-        <StyleInclude Source="avares://Avalonia.Themes.Default/Accents/BaseLight.xaml" />
+        <StyleInclude Source="avares://Avalonia.Themes.Simple/DefaultTheme.xaml" />
+        <StyleInclude Source="avares://Avalonia.Themes.Simple/Accents/Base.xaml" />
+        <StyleInclude Source="avares://Avalonia.Themes.Simple/Accents/BaseLight.xaml" />
     </Application.Styles>
 </Application>
diff --git a/tests/Avalonia.DesignerSupport.TestApp/Avalonia.DesignerSupport.TestApp.csproj b/tests/Avalonia.DesignerSupport.TestApp/Avalonia.DesignerSupport.TestApp.csproj
index f66b2b0457..278b0e087e 100644
--- a/tests/Avalonia.DesignerSupport.TestApp/Avalonia.DesignerSupport.TestApp.csproj
+++ b/tests/Avalonia.DesignerSupport.TestApp/Avalonia.DesignerSupport.TestApp.csproj
@@ -21,7 +21,7 @@
     <ProjectReference Include="..\..\src\Avalonia.Base\Avalonia.Base.csproj" />
     <ProjectReference Include="..\..\src\Avalonia.Controls\Avalonia.Controls.csproj" />
     <ProjectReference Include="..\..\src\Avalonia.Diagnostics\Avalonia.Diagnostics.csproj" />
-    <ProjectReference Include="..\..\src\Avalonia.Themes.Default\Avalonia.Themes.Default.csproj" />
+    <ProjectReference Include="..\..\src\Avalonia.Themes.Simple\Avalonia.Themes.Simple.csproj" />
     <ProjectReference Include="..\..\src\Avalonia.Desktop\Avalonia.Desktop.csproj" />
   </ItemGroup>
   <Import Project="..\..\build\BuildTargets.targets" />
diff --git a/tests/Avalonia.Direct2D1.RenderTests/Avalonia.Direct2D1.RenderTests.csproj b/tests/Avalonia.Direct2D1.RenderTests/Avalonia.Direct2D1.RenderTests.csproj
index 52acc78db1..4a90da77e7 100644
--- a/tests/Avalonia.Direct2D1.RenderTests/Avalonia.Direct2D1.RenderTests.csproj
+++ b/tests/Avalonia.Direct2D1.RenderTests/Avalonia.Direct2D1.RenderTests.csproj
@@ -13,7 +13,7 @@
     <ProjectReference Include="..\..\src\Markup\Avalonia.Markup\Avalonia.Markup.csproj" />
     <ProjectReference Include="..\..\src\Avalonia.Base\Avalonia.Base.csproj" />
     <ProjectReference Include="..\..\src\Avalonia.Controls\Avalonia.Controls.csproj" />
-    <ProjectReference Include="..\..\src\Avalonia.Themes.Default\Avalonia.Themes.Default.csproj" />
+    <ProjectReference Include="..\..\src\Avalonia.Themes.Simple\Avalonia.Themes.Simple.csproj" />
     <ProjectReference Include="..\..\src\Windows\Avalonia.Direct2D1\Avalonia.Direct2D1.csproj" />
   </ItemGroup>
   <Import Project="..\..\build\Moq.props" />
diff --git a/tests/Avalonia.LeakTests/Avalonia.LeakTests.csproj b/tests/Avalonia.LeakTests/Avalonia.LeakTests.csproj
index a00b24bdd7..4572f7ae7c 100644
--- a/tests/Avalonia.LeakTests/Avalonia.LeakTests.csproj
+++ b/tests/Avalonia.LeakTests/Avalonia.LeakTests.csproj
@@ -15,7 +15,7 @@
     <ProjectReference Include="..\..\src\Markup\Avalonia.Markup\Avalonia.Markup.csproj" />
     <ProjectReference Include="..\..\src\Avalonia.Base\Avalonia.Base.csproj" />
     <ProjectReference Include="..\..\src\Avalonia.Controls\Avalonia.Controls.csproj" />
-    <ProjectReference Include="..\..\src\Avalonia.Themes.Default\Avalonia.Themes.Default.csproj" />
+    <ProjectReference Include="..\..\src\Avalonia.Themes.Simple\Avalonia.Themes.Simple.csproj" />
     <ProjectReference Include="..\Avalonia.UnitTests\Avalonia.UnitTests.csproj" />
     <Compile Remove="testproject/**/*.cs" />
   </ItemGroup>
diff --git a/tests/Avalonia.Markup.Xaml.UnitTests/Avalonia.Markup.Xaml.UnitTests.csproj b/tests/Avalonia.Markup.Xaml.UnitTests/Avalonia.Markup.Xaml.UnitTests.csproj
index a0efa7bdeb..f562529cb8 100644
--- a/tests/Avalonia.Markup.Xaml.UnitTests/Avalonia.Markup.Xaml.UnitTests.csproj
+++ b/tests/Avalonia.Markup.Xaml.UnitTests/Avalonia.Markup.Xaml.UnitTests.csproj
@@ -18,7 +18,7 @@
     <ProjectReference Include="..\..\src\Markup\Avalonia.Markup\Avalonia.Markup.csproj" />
     <ProjectReference Include="..\..\src\Avalonia.Base\Avalonia.Base.csproj" />
     <ProjectReference Include="..\..\src\Avalonia.Controls\Avalonia.Controls.csproj" />
-    <ProjectReference Include="..\..\src\Avalonia.Themes.Default\Avalonia.Themes.Default.csproj" />
+    <ProjectReference Include="..\..\src\Avalonia.Themes.Simple\Avalonia.Themes.Simple.csproj" />
     <ProjectReference Include="..\Avalonia.UnitTests\Avalonia.UnitTests.csproj" />
   </ItemGroup>
   <ItemGroup>
diff --git a/tests/Avalonia.Markup.Xaml.UnitTests/Xaml/BasicTests.cs b/tests/Avalonia.Markup.Xaml.UnitTests/Xaml/BasicTests.cs
index 29148e6f2e..af2435a52f 100644
--- a/tests/Avalonia.Markup.Xaml.UnitTests/Xaml/BasicTests.cs
+++ b/tests/Avalonia.Markup.Xaml.UnitTests/Xaml/BasicTests.cs
@@ -466,7 +466,7 @@ namespace Avalonia.Markup.Xaml.UnitTests.Xaml
                 var xaml = @"
 <Styles xmlns='https://github.com/avaloniaui'
         xmlns:x='http://schemas.microsoft.com/winfx/2006/xaml'>
-    <StyleInclude Source='avares://Avalonia.Themes.Default/Controls/UserControl.xaml'/>
+    <StyleInclude Source='avares://Avalonia.Themes.Simple/Controls/UserControl.xaml'/>
 </Styles>";
 
                 var styles = AvaloniaRuntimeXamlLoader.Parse<Styles>(xaml);
diff --git a/tests/Avalonia.Skia.RenderTests/Avalonia.Skia.RenderTests.csproj b/tests/Avalonia.Skia.RenderTests/Avalonia.Skia.RenderTests.csproj
index d3f2b44968..5e481f21c1 100644
--- a/tests/Avalonia.Skia.RenderTests/Avalonia.Skia.RenderTests.csproj
+++ b/tests/Avalonia.Skia.RenderTests/Avalonia.Skia.RenderTests.csproj
@@ -14,7 +14,7 @@
     <ProjectReference Include="..\..\src\Markup\Avalonia.Markup\Avalonia.Markup.csproj" />
     <ProjectReference Include="..\..\src\Avalonia.Base\Avalonia.Base.csproj" />
     <ProjectReference Include="..\..\src\Avalonia.Controls\Avalonia.Controls.csproj" />
-    <ProjectReference Include="..\..\src\Avalonia.Themes.Default\Avalonia.Themes.Default.csproj" />
+    <ProjectReference Include="..\..\src\Avalonia.Themes.Simple\Avalonia.Themes.Simple.csproj" />
     <ProjectReference Include="..\..\src\Skia\Avalonia.Skia\Avalonia.Skia.csproj" />
   </ItemGroup>
   <Import Project="..\..\build\Moq.props" />
diff --git a/tests/Avalonia.UnitTests/Avalonia.UnitTests.csproj b/tests/Avalonia.UnitTests/Avalonia.UnitTests.csproj
index 52ef23c966..cb6884cad8 100644
--- a/tests/Avalonia.UnitTests/Avalonia.UnitTests.csproj
+++ b/tests/Avalonia.UnitTests/Avalonia.UnitTests.csproj
@@ -18,7 +18,7 @@
     <ProjectReference Include="..\..\src\Markup\Avalonia.Markup\Avalonia.Markup.csproj" />
     <ProjectReference Include="..\..\src\Avalonia.Base\Avalonia.Base.csproj" />
     <ProjectReference Include="..\..\src\Avalonia.Controls\Avalonia.Controls.csproj" />
-    <ProjectReference Include="..\..\src\Avalonia.Themes.Default\Avalonia.Themes.Default.csproj" />
+    <ProjectReference Include="..\..\src\Avalonia.Themes.Simple\Avalonia.Themes.Simple.csproj" />
   </ItemGroup>
   <Import Project="..\..\build\Moq.props" />
   <Import Project="..\..\build\Rx.props" />
diff --git a/tests/Avalonia.UnitTests/TestServices.cs b/tests/Avalonia.UnitTests/TestServices.cs
index c1be745aca..6a211d238e 100644
--- a/tests/Avalonia.UnitTests/TestServices.cs
+++ b/tests/Avalonia.UnitTests/TestServices.cs
@@ -6,7 +6,7 @@ using Avalonia.Markup.Xaml;
 using Avalonia.Media;
 using Avalonia.Platform;
 using Avalonia.Styling;
-using Avalonia.Themes.Default;
+using Avalonia.Themes.Simple;
 using Avalonia.Rendering;
 using System.Reactive.Concurrency;
 using System.Collections.Generic;
@@ -81,7 +81,7 @@ namespace Avalonia.UnitTests
             IScheduler scheduler = null,
             ICursorFactory standardCursorFactory = null,
             IStyler styler = null,
-            Func<Styles> theme = null,
+            Func<IStyle> theme = null,
             IPlatformThreadingInterface threadingInterface = null,
             IFontManagerImpl fontManagerImpl = null,
             ITextShaperImpl textShaperImpl = null,
@@ -122,7 +122,7 @@ namespace Avalonia.UnitTests
         public IScheduler Scheduler { get; }
         public ICursorFactory StandardCursorFactory { get; }
         public IStyler Styler { get; }
-        public Func<Styles> Theme { get; }
+        public Func<IStyle> Theme { get; }
         public IPlatformThreadingInterface ThreadingInterface { get; }
         public IWindowImpl WindowImpl { get; }
         public IWindowingPlatform WindowingPlatform { get; }
@@ -169,18 +169,9 @@ namespace Avalonia.UnitTests
                 windowImpl: windowImpl ?? WindowImpl);
         }
 
-        private static Styles CreateDefaultTheme()
+        private static IStyle CreateDefaultTheme()
         {
-            var result = new Styles
-            {
-                new DefaultTheme(),
-            };
-
-            var baseLight = (IStyle)AvaloniaXamlLoader.Load(
-                new Uri("avares://Avalonia.Themes.Default/Accents/BaseLight.xaml"));
-            result.Add(baseLight);
-
-            return result;
+            return new SimpleTheme { Mode = SimpleThemeMode.Light };
         }
 
         private static IPlatformRenderInterface CreateRenderInterfaceMock()
diff --git a/tests/Avalonia.UnitTests/UnitTestApplication.cs b/tests/Avalonia.UnitTests/UnitTestApplication.cs
index 63c2832b92..260771c9ab 100644
--- a/tests/Avalonia.UnitTests/UnitTestApplication.cs
+++ b/tests/Avalonia.UnitTests/UnitTestApplication.cs
@@ -71,12 +71,16 @@ namespace Avalonia.UnitTests
                 .Bind<IStyler>().ToConstant(Services.Styler)
                 .Bind<IWindowingPlatform>().ToConstant(Services.WindowingPlatform)
                 .Bind<PlatformHotkeyConfiguration>().ToSingleton<PlatformHotkeyConfiguration>();
-            var styles = Services.Theme?.Invoke();
+            var theme = Services.Theme?.Invoke();
 
-            if (styles != null)
+            if (theme is Styles styles)
             {
                 Styles.AddRange(styles);
             }
+            else if (theme is not null)
+            {
+                Styles.Add(theme);
+            }
         }
     }
 }