Newbie here - plz forgive protocol transgressions.
I originally misunderstood the Direct Child topic fairly completely. After carefully writing my question here, the answer came to me. Funny how that works. (Usually I have to hit submit before it all becomes clear.) I have now revised the question below to state my newfound assumptions about how Direct Child Selectors work. Perhaps someone could validate this for me, as it is still not firm in my mind. Thank you.
On p86, the direct child selector example has this selector: form > div > label to apply the rule float: left;.<br>
Based on the example at the top of p86, I (now) understand "direct child" and "immediate child" to mean, in this example, an immediately subordinate occurence of a div element within a form element, and within that div, an immediately subordinate occurence of a label element. Furthermore, to be a direct, or immediate child, there must be no "open" elements between the parent and child. The example (p86 top) has the strong element "breaking the chain" (my term) by being between the h2 and em elements, and by still being in effect (open, not closed) when the em element occurs. <br>
In the Try It Out, (p87) the h2 which appears between the form and div elements does not break the chain between the form and the div because the h2 is closed before the div occurs. Whew. <br>
Additionally, the subsequent divs in the example on p87 are affected because all subordinate divs (not just the first one, like I originally thought)are affected. And that's why all the divs are floating left in FF (not IE).
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