Set color for selected text?

[Edward Mendelson <em36@xxxxxxxxxxxx>]

Can anyone clarify how to set the screen color for selected text? For 
ordinary text, I use gray (called white in the help file) on blue. The 
default Highlight setting seems to be 16; this produces gray on black, 
which is almost indistinguishable from normal text's gray on blue. If I 
try 112, which shows up on the Color Choices menu as black on gray, what 
I get is not black on gray, but gray on brown.
Can anyone suggest a setting that would cause selected text to be the 
inverse of ordinary text, in this case blue on gray? None of the 
highlight colors that I choose actually produce that color in a document.

Many thanks to all.