problem with color background/font Export

[stu]

I use the Export PDF feature... which works fine with a
black text/white page setup... but, if I use a color
background, and a font color, export to PDF changes
the look of document, adding a white (or other color) border
all around the just edited document page.

Instead of this, I would like... or, what I expected was...
for the entire output page to be background color... except
of course for the font/text color.

Anybody know how to fix this... or, how to produce PDF
output like this, without the different border/margins color
being added ?