This particular text is pretty far into a chain of inheritance from multiply nested divs.
The div with class="hdr" contains a nested div with class="content". Then nested inside that div there is another with class="hdr.logo". Then inside that div you have two span tags around the text, each with a different class.
I agree with Longhaired_Genius on this one. The browser code that renders CSS is a fragile thing, and the earlier the browser version, the more fragile it gets.
To avoid confusing the rendering engine, try to simplify the div structure to include as little multiple nesting as possible. This also makes your code much easier to work on in the future.