How to define all textblock elements the same color

We are using global styles definitions for most of the types. We define then in the app.xaml file. When using TextBlock it is a problem to define a foreground color because it changes all the controls using TextBlock (Button's content color for example). How can we define a global style which will act only on specific TextBlock usages?

current problematic usage:

<Style TargetType={x:Type TextBlock}>
  <Setter Property="Foreground" Value="Red"/>
</Style>