Sic06/FrameworkLocal/UICore/Style/SeaBlue/GroupBoxStyle.xaml

<ResourceDictionary
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    xmlns:converters="clr-namespace:Aitex.Core.UI.Converters">

    <Style TargetType="GroupBox">
        <Setter Property="FontSize" Value="20" />
        <Setter Property="BorderBrush" Value="Black" />
    </Style>



    <converters:CenterBorderGapMaskConverter x:Key="BorderGapMaskConverter" />


    <Style x:Key="GroupboxWithoutWhiteBorder" TargetType="{x:Type GroupBox}">
        <Setter Property="BorderBrush" Value="#D5DFE5" />
        <Setter Property="BorderThickness" Value="1" />
        <Setter Property="Template">
            <Setter.Value>
                <ControlTemplate TargetType="{x:Type GroupBox}">
                    <Grid SnapsToDevicePixels="true">
                        <Grid.ColumnDefinitions>
                            <ColumnDefinition Width="6" />
                            <ColumnDefinition Width="Auto" />
                            <ColumnDefinition Width="*" />
                            <ColumnDefinition Width="6" />
                        </Grid.ColumnDefinitions>
                        <Grid.RowDefinitions>
                            <RowDefinition Height="Auto" />
                            <RowDefinition Height="Auto" />
                            <RowDefinition Height="*" />
                            <RowDefinition Height="6" />
                        </Grid.RowDefinitions>
                        <Border
                            Grid.Row="1"
                            Grid.RowSpan="3"
                            Grid.Column="0"
                            Grid.ColumnSpan="4"
                            Background="{TemplateBinding Background}"
                            BorderBrush="Transparent"
                            BorderThickness="{TemplateBinding BorderThickness}"
                            CornerRadius="4" />
                        <Border
                            Name="Header"
                            Grid.Row="0"
                            Grid.RowSpan="2"
                            Grid.Column="1"
                            Padding="3,1,3,0">
                            <ContentPresenter
                                ContentSource="Header"
                                RecognizesAccessKey="true"
                                SnapsToDevicePixels="{TemplateBinding SnapsToDevicePixels}" />
                        </Border>
                        <ContentPresenter
                            Grid.Row="2"
                            Grid.Column="1"
                            Grid.ColumnSpan="2"
                            Margin="{TemplateBinding Padding}"
                            SnapsToDevicePixels="{TemplateBinding SnapsToDevicePixels}" />
                        <Border
                            Grid.Row="1"
                            Grid.RowSpan="3"
                            Grid.ColumnSpan="4"
                            BorderBrush="{TemplateBinding BorderBrush}"
                            BorderThickness="{TemplateBinding BorderThickness}"
                            CornerRadius="3">
                            <Border.OpacityMask>
                                <MultiBinding Converter="{StaticResource BorderGapMaskConverter}" ConverterParameter="7">
                                    <Binding ElementName="Header" Path="ActualWidth" />
                                    <Binding Path="ActualWidth" RelativeSource="{RelativeSource Self}" />
                                    <Binding Path="ActualHeight" RelativeSource="{RelativeSource Self}" />
                                </MultiBinding>
                            </Border.OpacityMask>
                        </Border>
                    </Grid>
                </ControlTemplate>
            </Setter.Value>
        </Setter>
    </Style>


    <Style x:Key="GroupboxWithoutWhiteBorder2" TargetType="{x:Type GroupBox}">
        <Setter Property="BorderBrush" Value="#D5DFE5" />
        <Setter Property="BorderThickness" Value="1" />
        <Setter Property="FontSize" Value="20" />
        <Setter Property="Foreground" Value="White" />
        <Setter Property="Template">
            <Setter.Value>
                <ControlTemplate TargetType="{x:Type GroupBox}">
                    <Grid SnapsToDevicePixels="true">
                        <Grid.ColumnDefinitions>
                            <ColumnDefinition Width="6" />
                            <ColumnDefinition Width="Auto" />
                            <ColumnDefinition Width="*" />
                            <ColumnDefinition Width="6" />
                        </Grid.ColumnDefinitions>
                        <Grid.RowDefinitions>
                            <RowDefinition Height="Auto" />
                            <RowDefinition Height="Auto" />
                            <RowDefinition Height="*" />
                            <RowDefinition Height="6" />
                        </Grid.RowDefinitions>
                        <Border
                            Grid.Row="1"
                            Grid.RowSpan="3"
                            Grid.Column="0"
                            Grid.ColumnSpan="4"
                            Background="{TemplateBinding Background}"
                            BorderBrush="Transparent"
                            BorderThickness="{TemplateBinding BorderThickness}"
                            CornerRadius="4" />
                        <Border
                            x:Name="Header"
                            Grid.Row="0"
                            Grid.RowSpan="2"
                            Grid.Column="2"
                            Padding="3,1,3,0"
                            HorizontalAlignment="Center"
                            Grid.ZIndex="2">
                            <ContentPresenter
                                ContentSource="Header"
                                RecognizesAccessKey="True"
                                SnapsToDevicePixels="{TemplateBinding SnapsToDevicePixels}" />
                        </Border>
                        <ContentPresenter
                            Grid.Row="2"
                            Grid.Column="1"
                            Grid.ColumnSpan="2"
                            Margin="{TemplateBinding Padding}"
                            SnapsToDevicePixels="{TemplateBinding SnapsToDevicePixels}" />
                        <Border
                            Grid.Row="1"
                            Grid.RowSpan="3"
                            Grid.ColumnSpan="4"
                            BorderBrush="{TemplateBinding BorderBrush}"
                            BorderThickness="{TemplateBinding BorderThickness}"
                            CornerRadius="3">
                            <Border.OpacityMask>
                                <MultiBinding Converter="{StaticResource BorderGapMaskConverter}" ConverterParameter="7">
                                    <Binding ElementName="Header" Path="ActualWidth" />
                                    <Binding Path="ActualWidth" RelativeSource="{RelativeSource Self}" />
                                    <Binding Path="ActualHeight" RelativeSource="{RelativeSource Self}" />
                                </MultiBinding>
                            </Border.OpacityMask>
                            <!--<Border BorderBrush="{TemplateBinding BorderBrush}" BorderThickness="{TemplateBinding BorderThickness}" CornerRadius="3">
                                <Border BorderBrush="White" BorderThickness="{TemplateBinding BorderThickness}" CornerRadius="2"/>
                            </Border>-->
                        </Border>
                    </Grid>
                </ControlTemplate>
            </Setter.Value>
        </Setter>
    </Style>
</ResourceDictionary>