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.
Copyright © 2002 O'Reilly & Associates. All rights reserved.DIV. As we can see, the end of theDIV is actually above the visual bottom of itschild paragraph. The next element after the DIV isthe appropriate distance from the bottom of theDIV. The fact that it overlaps the paragraphdoesn't matter, at least not technically.
Now let's consider an example where the margins of a list item,an unordered list, and a heading are all collapsed. In this case, theunordered list and heading will be set to have negative margins: