kmpdfkit_demo/Demo/Examples/Compdfkit.Controls/Asset/Styles/WindowStyle.xaml

<ResourceDictionary xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
    <Style x:Key="WindowStyle" TargetType="{x:Type Window}">
        <Setter Property="WindowChrome.WindowChrome">
            <Setter.Value>
                <WindowChrome
                    CaptionHeight="32"
                    CornerRadius="0"
                    GlassFrameThickness="0"
                    ResizeBorderThickness="5"
                    UseAeroCaptionButtons="False" />
            </Setter.Value>
        </Setter>
        <Setter Property="Template">
            <Setter.Value>
                <ControlTemplate TargetType="{x:Type Window}">
                    <Border
                        Background="{TemplateBinding Background}"
                        BorderBrush="{TemplateBinding BorderBrush}"
                        BorderThickness="{TemplateBinding BorderThickness}">
                        <AdornerDecorator>
                            <ContentPresenter x:Name="win_content" />
                        </AdornerDecorator>
                    </Border>
                    <ControlTemplate.Triggers>
                        <Trigger Property="WindowState" Value="Maximized">
                            <Setter TargetName="win_content" Property="Margin" Value="5,5,5,5" />
                        </Trigger>
                    </ControlTemplate.Triggers>
                </ControlTemplate>
            </Setter.Value>
        </Setter>
    </Style>
</ResourceDictionary>