Styles with Trigger on IsMouseOver still shows the winfows blue color

Right now I'm trying to use styles in my very new wpf solution.

 

I have problems with the Trigger IsMouseOver background color. Even when using another background color it still shows Windows blue on mouse over. Do I have to set another property for the mouse over blue color?

 

Can anyone tell me, why I can make the style Bold but not cann't change the windows normal blue color on mouseover a button?

 

I have attached the solution

 

But here is the code first my app.xaml file

And here is my

 

My MainWindow (the two first images are logos You can put every image you want. The Divider image is included in the solution.

Best regards,

Simsen :-)