Global %%add-css blocks

[Jerry Malcolm]

Dirk, et al.... now a question that is completely unrelated to the 
previous saga....  I would like to change the upper left logo to my 
client's site logo.  I read the doc about how to do this using the 
%%add-css blocks.  But from what I can tell in the documentation, it 
appears that I have to re-add that same block of code to every page in 
the entire wiki.  I couldn't find an explanation or example of how to do 
it globally.  Is it true that i need to add that entire block of code to 
every page that I want to change the logo on (which is every page in the 
entire wiki)  Or is there a way to add that %%add-css code once and have 
it apply across all pages?

Thx again.
Jerry