CSS selecting a div after a div with a div

Question

I have this code on a login page:

<div id="header">
    <div id="homeBanner">
        ...
    </div>
</div>
<div id="navigation">
    ...
</div>

I'd like to select div#navigation but only when it follows div#header that contains div#homeBanner. The reason is I have similar code on a different page:

<div id="header">
    <div id="siteBanner">
        ...
    </div>
</div>
<div id="navigation">
    ...
</div>

I don't want to affect the style of div#navigation when it follows div#header that contains div#siteBanner. Does this make sense?

How do I select div#navigation only when it follows div#header that contains div#homeBanner? I thought it was:

div#header div#homeBanner > div#navigation

... but that doesn't seem to work.

Answer 1

Problem here is that you're trying to select the sibling of a parent element based on the parent's child, which isn't possible in CSS.

Your best bet is to add a class to #header (or even body) based on that information then make use of that class.

For example:

<div id="header" class="home">
    <div id="homeBanner">
        ...
    </div>
</div>
<div id="navigation">
    ...
</div>

With this selector (as mentioned by others, use + for siblings, not > for children):

#header.home + #navigation