I believe you're referring to LESS
I am sorry if this is a novice question, I am just getting into a lot of this stuff. When I was looking through some of the files, figuring out where to change pictures and text, I remember seeing something about lesser files(might be called something else). I am going to use Aptana to manipulate everything and wanted to see if someone could give me a little in site as to where these files are or what the definition is of this. Again, I apologize for the novice question.
Hi Patt,
I'm almost certain you're referring to LESS files.
When you open up "about-custom-themes.md" located in the /assets/default directory, the file says:
Customizng Your Theme
====
When modifying the default theme, it is recommended that you do not
edit the CSS files directly. Instead, you should use the included
LESS files and recompile the CSS file with your edits.
Even if you decide to edit the CSS directly, we recommend that you
keep the LESS files, so that you can quickly rebuild the default
theme should you need to recover it, or for upgrade purposes.
*Please do not submit any CSS edits to the official branch, unless
they are done within the LESS files.*
...which is an interesting message considering there's no .less files to be found. Not sure what happened here.