When it comes right down to it, positioning is a very compelling technology. It's also likely to be an exercise in frustration if you're trying to get it to behave consistently in a cross-browser environment. The problem isn't so much that it won't work in some browsers: it's that it will only sort of work in a number of them, such as Navigator 4 and Internet Explorer 4 and 5. It can be great fun to play with positioning, and one day we'll be able to use it in place of tables and frames while dramatically improving accessibility and backward compatibility. As of this writing, though, it remains a great way to create design prototypes, but a tricky thing to use on a public web site.
As it happens, this sentiment may be applied to the majority of CSS2, which is given an overview in the next chapter.
<TABLE CELLSPACING=0><TR><TD>sidebar</TD><TD>navigation bar and main display</TD></TR></TABLE>
We'll turn to the sidebar first. Each set of links is groupedinto a list under a main heading; these headings look different fromthe links. Each of the sections uses the following tags:
Copyright © 2002 O'Reilly & Associates. All rights reserved.implementation-specific limits." In the world of web browsers,though Navigator 4.x, Explorer 4.x/5.x, and Opera 3.x do permitnegative margins:
Negative margins have an impact on vertical formatting, affecting howmargins are collapsed. If there are negative vertical margins, thenthe browser should take the absolutemaximum of the negative margins and subtract that from the maximum ofany positive margins.