Where do I change the colour of the outlier selection?

Help! I’ve lost where to change the colour that makes the nice round rectangle to highlight the selected text in outliner mode.

It must be possible as mine is salmon coloured and the screen-shots are all blue like here: literatureandlatte.com/screens5.html

But I can’t find it anywhere…

Apple Menu/System Preferences/Appearance Highlight Color.

Dave

Aha! Thanks.