Hello! I am using the following code for my program. I want it to look like Office 2013, you should only add the reference to the project that comes with WPF 4.5 and is System.Windows.Controls.Ribbon. I have a problem, when I select one tab, her border, its not completed.

Code:
<Window x:Class="WpfApplication1.MainWindow"
            xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
            xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
            WindowStartupLocation="CenterScreen">

        <Window.Resources>

            <Style TargetType="Ribbon">
                <Setter Property="Background" Value="White"/>
                <Setter Property="Foreground" Value="Black"/>
                <!--<Setter Property="BorderBrush" Value="{x:Null}"/>-->
                <!-- TODO Template 

                But how does this work? :/
            -->
            </Style>

            <Style TargetType="RibbonGroup">
                <Setter Property="Background" Value="Transparent"/>
                <!--<Setter Property="MouseOverBackground" Value="Transparent"/>
                <Setter Property="MouseOverBorderBrush" Value="Transparent"/>-->
            </Style>



            <Style TargetType="RibbonTabHeader">
                <Setter Property="Background" Value="White"/>
                <Setter Property="BorderBrush" Value="Transparent"/>
                <Setter Property="FontSize" Value="13"/>
                <Setter Property="Padding" Value="15,2,15,2"/>
                <Setter Property="BorderThickness" Value="1,1,1,5"/>
                <Setter Property="Margin" Value="1,0,1,0"/>
                <Setter Property="Template">
                    <Setter.Value>
                        <ControlTemplate TargetType="RibbonTabHeader">
                            <ControlTemplate.Resources>
                                <SolidColorBrush x:Key="CheckedBackground" Color="#FFF5F6F7"/>
                                <SolidColorBrush x:Key="CheckedBorderBrush" Color="#FFDBDCDD"/>
                                <!--<SolidColorBrush x:Key="FocusedBackground" Color="#FFFDFDFF"/>
                                <SolidColorBrush x:Key="FocusedBorderBrush" Color="#FFEDEEEE"/>
                                <SolidColorBrush x:Key="MouseOverBackground" Color="#FFFDFDFF"/>
                                <SolidColorBrush x:Key="MouseOverBorderBrush" Color="#FFEDEEEE"/>-->
                            </ControlTemplate.Resources>

                            <Border Background="{TemplateBinding Background}" BorderBrush="{TemplateBinding BorderBrush}" BorderThickness="{TemplateBinding BorderThickness}">
                                <ContentPresenter Margin="{TemplateBinding Padding}" HorizontalAlignment="Center" VerticalAlignment="Center" RecognizesAccessKey="True"/>
                            </Border>

                    <ControlTemplate.Triggers>
                        <Trigger Property="IsRibbonTabSelected" Value="True">
                            <Setter Property="Background" Value="{DynamicResource CheckedBackground}"/>
                            <!--<Setter Property="BorderBrush" Value="{DynamicResource CheckedBorderBrush}"/>-->
                            <Setter Property="BorderBrush" Value="#FFB9C9DA"/>
                            <Setter Property="Foreground" Value="Blue"/>
                        </Trigger>
                        <Trigger Property="IsMouseOver" Value="True">
                            <!--<Setter Property="Background" Value="{DynamicResource CheckedBackground}"/>-->
                            <!--<Setter Property="BorderBrush" Value="{DynamicResource CheckedBorderBrush}"/>-->
                            <!--<Setter Property="BorderBrush" Value="#FFB9C9DA"/>-->
                            <Setter Property="Foreground" Value="Blue"/>
                        </Trigger>
                        <!--<MultiTrigger>
                            <MultiTrigger.Conditions>
                                <Condition Property="IsRibbonTabSelected" Value="False"/>
                                <Condition Property="IsMouseOver" Value="True"/>
                            </MultiTrigger.Conditions>
                            <Setter Property="Background" Value="{DynamicResource MouseOverBackground}"/>
                            <Setter Property="BorderBrush" Value="{DynamicResource MouseOverBorderBrush}"/>
                        </MultiTrigger>-->
                    </ControlTemplate.Triggers>
                        </ControlTemplate>
                    </Setter.Value>
                </Setter>
            </Style>

        </Window.Resources>

        <Grid>

            <Ribbon>
                <RibbonTab Header="INICIO">
                    <RibbonGroup Header="Portapapeles">
                        <RibbonButton Label="Hola" LargeImageSource="Imágenes/ArtÃ*culo.png" Height="Auto" VerticalAlignment="Top"/>
                    </RibbonGroup>
                    <RibbonGroup Header="Fuente">
                        <RibbonButton Content="Fuente"/>
                    </RibbonGroup>
                </RibbonTab>
                <RibbonTab Header="INSERTAR"/>
                <RibbonTab Header="DISEÑO"/>
                <Ribbon.ApplicationMenu>
                    <RibbonApplicationMenu SmallImageSource="Imágenes/Usuario.png">
                        <RibbonApplicationMenuItem Width="Auto" Header="Iniciar sesión..." ImageSource="Imágenes/Usuario.png"/>
                        <RibbonApplicationMenuItem Width="Auto" Header="Cambiar contraseña..." ImageSource="Imágenes/Usuario.png"/>
                        <RibbonApplicationMenuItem Width="Auto" Header="Cerrar sesión..." ImageSource="Imágenes/Usuario.png"/>
                    </RibbonApplicationMenu>
                </Ribbon.ApplicationMenu>
            </Ribbon>

        </Grid>
    </Window>
Attached 2 images, the first is what I get done, the other is what I would like.
Name:  640789.jpg
Views: 612
Size:  10.8 KB

Name:  640787.jpg
Views: 652
Size:  9.6 KB

Thx!!!