Dobra. Już ogarnąłem temat. Może komuś się przyda:
<Window.Resources>
<Style x:Key="Triggersy" TargetType="Button">
<Setter Property="Background" Value="Brown"/>
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="{x:Type Button}">
<Border Background="{TemplateBinding Background}">
<ContentPresenter HorizontalAlignment="Center" VerticalAlignment="Center"/>
</Border>
<ControlTemplate.Triggers>
<Trigger Property="IsMouseOver" Value="True">
<Setter Property="Background" Value="White"/>
</Trigger>
</ControlTemplate.Triggers>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
</Window.Resources>
<DockPanel>
<Button DockPanel.Dock="Left" Content="gngurgoo" Style="{StaticResource Triggersy}" Width="100"/>
</DockPanel>
<Window.Resources>
<Style x:Key="Triggersy" TargetType="Button">
<Setter Property="Background" Value="Brown"/>
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="{x:Type Button}">
<Border Background="{TemplateBinding Background}">
<ContentPresenter HorizontalAlignment="Center" VerticalAlignment="Center"/>
</Border>
<ControlTemplate.Triggers>
<Trigger Property="IsMouseOver" Value="True">
<Setter Property="Background" Value="White"/>
</Trigger>
</ControlTemplate.Triggers>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
</Window.Resources>
<DockPanel>
<Button DockPanel.Dock="Left" Content="gngurgoo" Style="{StaticResource Triggersy}" Width="100"/>
</DockPanel>