Change a Style based on Visual State - wpf

Question

"Blend makes it simple to setup Visual States based on say minWindowWidth. But it would be very nice to have state-based Styles defined for TextBlock elements, say with tag="header", tag="body", and have the Setter change the Style automatically."
Maybe I wasn't explicit enough in my initial question, let me rephrase this.
I am resizing my application window from say Landscape to Portrait. My VisualStateManager has setters which adjust the page properties based on the new minimum width.
I have multiple TextBlocks (header,body, etc) and other controls with .Text (ToggleSwitch), that I want to automatically adjust FontSize based on the new width.
Aside from manually setting every single control by name in all the states, is there a way to have the VisualStateManager do it automatically for each 'type' of Text(body/header/etc)? My work around at the moment is to DataBind a Style for every .Text control and have the ViewModel do all the scaling. That works, but this is really something Blend is made for, right? So I must be missing the obvious way everyone is using.
Thanks for all the good comments so far.
<VisualStateManager.VisualStateGroups>
<VisualStateGroup x:Name="VisualStateGroup">
<VisualState x:Name="PhonePortrait">
<VisualState.StateTriggers>
<AdaptiveTrigger MinWindowWidth="{StaticResource NarrowMinWidth}"/>
</VisualState.StateTriggers>
<VisualState.Setters>
<Setter Target="SwitchStackPanel.(StackPanel.Orientation)" Value="Vertical"/>
<!-- Setter to change all Body textblocks to FontSize=8-->
<!-- Setter to change all Header textblocks to FontSize=10-->
<!-- Setter to change all ToggleSwitch.Text to FontSize=8-->
<!-- etc..-->

Answer 1

You could use a global style. That utilizes triggers based on the Tag.
<Style TargetType="{x:Type TextBlock}">
<!--Default Setters Here-->
<Setter Property="Background" Value="White"/>
<Style.Triggers>
<Trigger Property="Tag" Value="body">
<Setter Property="Background" Value="Gray"/>
<!--Insert desired state setters here-->
</Trigger>
<Trigger Property="Tag" Value="header">
<Setter Property="Background" Value="DarkGray"/>
<!--Insert desired state setters here-->
</Trigger>
</Style.Triggers>
</Style>
You can then have a default state, and Triggered setters than only affect a Textblock when an applicable tag is attached.
If you already have other styles or want to have a selection process, you may want to add a key and then use BasedOn within the style.