Styling RadioButton In UWP

Question

I have styled my radio Button to create a color picker. I have removed the content property of radio button and some other styling. See below. Expected Behavior:Only the ellipse without the padding space around it. But i am getting extra space around the ellipse even after setting width and height of the radio button. What I'm doing wrong?

My XAML:

    <RadioButton x:Name="Blue" Tag="0" Width="32" Height="32"
                 RelativePanel.AlignTopWithPanel="True" 
                 RelativePanel.AlignLeftWithPanel="True"
                 GroupName="ColorPicker"
                 Background="#C6F5F9" Checked="Color_Checked" Style="{StaticResource ColorPickerStyle}"/>

My Radio Button Style:

<Style x:Key="ColorPickerStyle" TargetType="RadioButton">
    <Setter Property="Background" Value="{ThemeResource RadioButtonBackground}"/>
    <Setter Property="Foreground" Value="{ThemeResource RadioButtonForeground}"/>
    <Setter Property="BorderBrush" Value="{ThemeResource RadioButtonBorderBrush}"/>
    <Setter Property="Margin" Value="4,4,4,4"/>
    <Setter Property="FontFamily" Value="{ThemeResource ContentControlThemeFontFamily}"/>
    <Setter Property="FontSize" Value="{ThemeResource ControlContentThemeFontSize}"/>
    <Setter Property="UseSystemFocusVisuals" Value="True"/>
    <Setter Property="FocusVisualMargin" Value="-7,-3,-7,-3"/>
    <Setter Property="Template">
        <Setter.Value>
            <ControlTemplate TargetType="RadioButton">
                <Grid x:Name="RootGrid" Width="{TemplateBinding Width}" Height="{TemplateBinding Height}" Background="Transparent">
                    <VisualStateManager.VisualStateGroups>
                        <VisualStateGroup x:Name="CommonStates">
                            <VisualState x:Name="Normal"/>
                            <VisualState x:Name="Pressed">
                                <Storyboard>
                                    <ObjectAnimationUsingKeyFrames Storyboard.TargetProperty="Visibility" Storyboard.TargetName="CheckGlyph">
                                        <DiscreteObjectKeyFrame KeyTime="0" Value="Visible"/>
                                    </ObjectAnimationUsingKeyFrames>
                                </Storyboard>
                            </VisualState>
                            <VisualState x:Name="Disabled">
                                <Storyboard>
                                    <ObjectAnimationUsingKeyFrames Storyboard.TargetProperty="Visibility" Storyboard.TargetName="CheckGlyph">
                                        <DiscreteObjectKeyFrame KeyTime="0" Value="Collapsed"/>
                                    </ObjectAnimationUsingKeyFrames>
                                </Storyboard>
                            </VisualState>
                        </VisualStateGroup>
                        <VisualStateGroup x:Name="CheckStates">
                            <VisualState x:Name="Checked">
                                <Storyboard>
                                    <ObjectAnimationUsingKeyFrames Storyboard.TargetProperty="Visibility" Storyboard.TargetName="CheckGlyph">
                                        <DiscreteObjectKeyFrame KeyTime="0" Value="Visible"/>
                                    </ObjectAnimationUsingKeyFrames>
                                </Storyboard>
                            </VisualState>
                            <VisualState x:Name="Unchecked">
                                <Storyboard>
                                    <ObjectAnimationUsingKeyFrames Storyboard.TargetProperty="Visibility" Storyboard.TargetName="CheckGlyph">
                                        <DiscreteObjectKeyFrame KeyTime="0" Value="Collapsed"/>
                                    </ObjectAnimationUsingKeyFrames>
                                </Storyboard>
                            </VisualState>
                            <VisualState x:Name="Indeterminate"/>
                        </VisualStateGroup>
                    </VisualStateManager.VisualStateGroups>
                    <Ellipse x:Name="OuterEllipse" Stroke="Black" StrokeThickness="2" Width="{TemplateBinding Width}" Fill="{TemplateBinding Background}" Height="{TemplateBinding Height}" UseLayoutRounding="False"/>
                    <FontIcon x:Name="CheckGlyph" FontSize="16" Height="16" Width="16" Glyph="&#xE8FB;" 
                                      UseLayoutRounding="False" AutomationProperties.Name="Select"/>
                </Grid>
            </ControlTemplate>
        </Setter.Value>
    </Setter>
</Style>

Answer 1

Setting the MinWidth and MinHeight property to 0 fixed the issue.