Touch-up record detail extras display

1) Remove unsightly gaps, which gave it an overly "stripey"
appearance.

2) Switch off-green arrow graphic with a text-based arrow character.

3) Simplify unnecessarily complex positioning styles.

4) Lighten and add subtle border to give depth and definition to
section headers.

Signed-off-by: Dan Wells <dbw2@calvin.edu>
Signed-off-by: Dan Scott <dscott@laurentian.ca>