I'm not sure the best way to setup my HTML/CSS to get different styling on different pages.

Let's say I have a top menu with Foo, Bar and Baz. I want the top menu rendered basically the same on each page, but on the Foo, page I want Foo to be slightly different:

FOO Bar Baz

and on the Bar page, Bar should stand out:

Foo BAR Baz

I could either use different CSS for each page, or different HTML:

A) Use a different style sheet for each page so the CSS controls the rendering

B) Use a different class on the "current" page in the HTML, something like:

<li>Foo</li>
<li class="bar">Bar</li>
...

Is there any advantage to one method or the other?