I love the application but the CSS drives me nuts.
Some suggestions
Use ID instead of class at the template level and page level so we can eliminate a lot of the nesting and eliminate a lot of classes and make it much more readable.
#Global (at the template)
(Page level)
#Page_Products
#Page_Categories
#Page_Topic etc.
Instead of Classes for the headings it would be preferable to use H1 for page headings or at least
#Global H1{}
#Global H2{}
#Global p{}
You can overide at the page level.
Example:
<html>
<style>
#Global H1{Font-size:20pt}
#Global H2{color:green}
#Page_Products H1{Font-size:15pt; color:red}
</style>
<div id="Global">
<h1>Test Global Heading</h1>
<h2>Test H2 Global</h2>
<div id="Page_Products">
<h1>Test Page_Products Heading</h1>
<h2>Test H2 Page_Products</h2>
<div>
</html>
Just some food for thought