RE: Horizontal rules

> Internet Explorer treats the HR as a different 'display' type, not
> as a block.  The HR display type (I don't know if it has a name, that
> is, whether maybe you could use that display type in XML) makes odd
> uses of some CSS properties.  'color', not 'background-color', sets
> the color inside the box, and 'height' is the height of the BR
> including the borders (normally in CSS, the 'height' does not include
> borders.)
Always in fact.
>  'text-align' positions the HR horizontally within the
> available space.
No. IE's acceptance of text-align on horizontal rule completely destroys
its horizontal rule implementation from a CSS standpoint.

It is as ridiculous to allow text-align to affect horizontal rules as it
is to allow it to affect the border of P {border: solid} - text-align
affects inline content (not just text, incidentally) within line boxes
where the inline content is less wide than the line box.

The margin: auto thing is not difficult to understand because browsers
should have it in their UA style sheet (Mozilla does) so it need not
trouble those who do not understand these things (it should also be in
the sample style sheet for CSS incidentally).

The HTML align=left attribute is equivalent to margin-left: 0;
margin-right: auto (N.B. not 0), align=right to margin-right: auto;
margin-left: 0 and align=center (the default) to margin-right: auto;
margin-left: auto. 
> This is sort of intuitive, unless you're a CSS expert, in which case it is 

very stupid indeed.
To see what I mean, try something as trivial as margin-right: 50%
(heaven forfend that you should try setting both margins), which should
set a width of 50% - it doesn't (far from it).