This image shows split windows, with the Gnus Summary buffer on top and
the Article buffer below.  The mode line of the Summary buffer has my
customized mode-line face (Helvetica font as in variable-pitch face,
plus over- and underlining).  The mode line of the Article buffer has
mode-line-inactive face, which inherits from mode-line but overrides the
weight attribute, making it light.  The Article buffer also has a header
line from the tabbar library, which I've customized with font Helvetica,
width compressed, height 85 in 1/10 pt and weight medium (and it also
shows the over- and underlining from my customized header-line face --
note the underlining is unbroken, in constrast to that of the mode-line
face).

Steve Berman