контен по центру формы

MainWindow.xaml

@@ -5,8 +5,19 @@
         xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
         xmlns:local="clr-namespace:savelev_avtor"
         mc:Ignorable="d"
-        Title="MainWindow" Height="460" Width="800">
-    <Grid>
-        
+        Title="MainWindow" Height="450.186" Width="821.655">
+    <Grid RenderTransformOrigin="0.484,0.497">
+        <Grid.RowDefinitions>
+            <RowDefinition Height="111*"/>
+            <RowDefinition Height="235*"/>
+            <RowDefinition Height="111*"/>
+        </Grid.RowDefinitions>
+        <Grid.ColumnDefinitions>
+            <ColumnDefinition Width="222*"/>
+            <ColumnDefinition Width="295*"/>
+            <ColumnDefinition Width="222*"/>
+        </Grid.ColumnDefinitions>
+        <Grid HorizontalAlignment="Left" Height="100" Margin="190,85,0,0" VerticalAlignment="Top" Width="100" RenderTransformOrigin="0.305,0.706" Grid.Column="1" Grid.Row="1"/>
+
     </Grid>
 </Window>