[dba-Tech] Word Question about Styles

I've been trying without success to create a dot file formatted like various
manuals and PDF files I have seen, and I can't figure out how to do it. The
look that I want has a line has headings progressively indented, with the
normal text indended even more. That part is easy enough. But I want to add
a line above (or below) the headings such that the line runs all the way to
the right margin, irrespective of how much text there is. Trying line-above
or line-below results in a line exactly as long as the text itself, and
that's not what I want.

Any ideas how to do this?

TIA,
Arthur