Horizontal rule attributes and margins

Each rule sits in a grey band. A rule has 0.5em above and below by default, and centres when it is narrower than the band; align moves it by changing those margins, and an author margin overrides both.

default
width="50%"
width="50%" align="left"
width="50%" align="center"
width="50%" align="right"
align="right" + margin: 0
hr { margin: 0 } between text

above

below

hr default between text

above

below

size="1"
size="3"
size="10"
size="10" noshade
size="10" color="red"
size="10" color="#2a7" width="50%" align="right"