How do you change the color of a row when you select it in a table?

[kieranwalsh]

I've gone through all the Example-Table data I think and in every one when you select a row in a table it turn blue. I want to change this. It feels like this should do it:

New-HTMLTableStyle -Type RowSelected -TextColor '#ffffff' -BackgroundColor '#25006D'

but it doesn't seem to make any difference.