How to style a WPF Expander Header?

Question

I would like to apply a style on a WPF Expander Header. In the following XAML I have an Expander but the style is for all of it not just for the header.

Thanks.

Answer 1

I have combined some XAML from Josh Smith and MSDN and came up with a solution. Indeed, the control (al least the header) must be retemplated.

    
        

            

            
                
                    
                
            

            

        

        
            
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