如何在不切断选项卡的情况下为我的WPF TabItem添加水平边距？

<TabControl Margin="10,0,10,0">
    <TabItem Header="TabItem1">
        <!-- 内容 -->
    </TabItem>
    <TabItem Header="TabItem2">
        <!-- 内容 -->
    </TabItem>
</TabControl>

<TabControl>
    <TabItem>
        <TabItem.Header>
           <StackPanel Orientation="Horizontal">
                <TextBlock Margin="10,0,0,0" Text="TabItem1"/>
            </StackPanel>
        </TabItem.Header>
        <!-- 内容 -->
    </TabItem>
    <TabItem>
        <TabItem.Header>
           <StackPanel Orientation="Horizontal">
                <TextBlock Margin="10,0,0,0" Text="TabItem2"/>
            </StackPanel>
        </TabItem.Header>
        <!-- 内容 -->
    </TabItem>
</TabControl>

<TabControl>
    <TabControl.Resources>
       <Style TargetType="TabItem">
           <Setter Property="Template">
               <Setter.Value>
                   <ControlTemplate TargetType="TabItem">
                        <Grid>
                           <Border Name="Border" Margin="10,0,10,0" BorderThickness="1,1,1,0" CornerRadius="4,4,0,0" Background="{TemplateBinding Background}">
                               <ContentPresenter ContentSource="Header" Margin="10,5,10,5"/>
                            </Border>
                        </Grid>
                       <ControlTemplate.Triggers>
                           <Trigger Property="IsSelected" Value="True">
                               <Setter TargetName="Border" Property="Background" Value="{DynamicResource {x:Static SystemColors.ControlLightLightBrushKey}}"/>
                               <Setter TargetName="Border" Property="BorderThickness" Value="1,1,1,0"/>
                            </Trigger>
                           <Trigger Property="IsSelected" Value="False">
                               <Setter TargetName="Border" Property="Background" Value="{DynamicResource {x:Static SystemColors.ControlBrushKey}}"/>
                               <Setter TargetName="Border" Property="BorderThickness" Value="1,1,1,0"/>
                            </Trigger>
                        </ControlTemplate.Triggers>
                    </ControlTemplate>
                </Setter.Value>
            </Setter>
        </Style>
    </TabControl.Resources>
    <TabItem Header="TabItem1">
        <!-- 内容 -->
    </TabItem>
    <TabItem Header="TabItem2">
        <!-- 内容 -->
    </TabItem>
</TabControl>