kmpdfkit_demo/compdfkit_demo_windows/compdfkit/compdfkit-assets/Styles/ButtonStyle.xaml

<ResourceDictionary xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
    <Style x:Key="TransparentButtonStyle" TargetType="{x:Type Button}">
        <Setter Property="Background" Value="Transparent"/>
        <Setter Property="BorderBrush" Value="Transparent"/>
        <Setter Property="Foreground" Value="White"/>
        <Setter Property="Template">
            <Setter.Value>
                <ControlTemplate TargetType="{x:Type Button}">
                    <Border x:Name="border"
                            Background="{TemplateBinding Background}"
                            BorderBrush="{TemplateBinding BorderBrush}"
                            BorderThickness="{TemplateBinding BorderThickness}">
                        <ContentPresenter HorizontalAlignment="Center"
                                          VerticalAlignment="Center"/>
                    </Border>
                    <ControlTemplate.Triggers>
                        <Trigger Property="IsMouseOver" Value="True">
                            <Setter TargetName="border" Property="Background" Value="#4C000000"/>
                            <Setter TargetName="border" Property="BorderBrush" Value="White"/>
                        </Trigger>
                        <Trigger Property="IsPressed" Value="True">
                            <Setter TargetName="border" Property="Background" Value="#80000000"/>
                            <Setter TargetName="border" Property="BorderBrush" Value="White"/>
                        </Trigger>
                    </ControlTemplate.Triggers>
                </ControlTemplate>
            </Setter.Value>
        </Setter>
    </Style>
</ResourceDictionary>