I know how to change the background color of the scroll bar:
<ScrollBar Height="27" Margin="36,96,12,0" Name="scrollBar1" Background="Red"></ScrollBar>
here is a photo with my red background: 
How can I do the same with ScrollViewer? I have a grid inside my ScrollViewer, and if I change the properties of the ScrollViewer, it looks like it changes the properties of the content inside my grid.
<ScrollViewer> <Grid Name="Parent"> <Grid.RowDefinitions> <RowDefinition Height="Auto" /> <RowDefinition Height="Auto" /> .... .... ... etc
which produces:

with the contents of my grid named "Parent" on the left. How can I put a red background on this ScrollViewer?
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