Use SASS/Compass, for realzies.
I'm relatively new to web design and coding (approaching two years in from the time I decided to augment my English Literature education by learning some tech skills).
Of course I began with a CMS. Of course it was Wordpress. Then, of course, I graduated to Drupal, but I felt boxed-in using all those GUIs and contributed themes and modules. I've always romanticized the coders. Perhaps it's Hollywood's fault, but the idea of a guy (or girl) sitting at his (or her) computer and hacking away at the world just seemed really bad-ass to me. And you know, I need very little instigation to dive head-first into something new and become completely obsessed with it.
So, what definitely is bad-ass? Yes, learning to code.
Once you get comfortable with HTML and standard CSS, you definitely should think about getting familiar with your command line terminal. Just the basics will do. Learn a little bit every day. Today, learn what your command line actually is (it's a place where you type commands to tell your computer, directly, to do things you want it to do). Tomorrow, embark upon your first tour of your file structure, via the 'ls' and 'cd' commands.
If you're waiting for me to get to the point, it's this: use SASS/Compass to write better style sheets. (Why did I talk about terminal? Well, you install Compass via the terminal. Or, if you'd prefer to keep it GUI, check out the Scout app.)
What is SASS? Syntactically Awesome Style Sheets. What is Compass? A collection of helpers and mixins to make SASS even more awesome. They go hand-in-hand, somewhat similar to javascript and jQuery.
SASS is not hard to learn because it's built on CSS and you only have to use SASS when you want to (which should be often).
There is a ton of great documentation to get you started, so I won't explain the language here, but quickly, some things it offers:
Variables, Mixins, Nesting, Selector Inheritance, Cross-browser support, Typographic Rhythms, Sprites
Once you get the hang of it, you'll never write normal CSS again. It's a huge time-saver, especially for cross-browser compatibility issues, and makes your CSS smarter! Check out these resources for more:
http://sass-lang.com, http://compass-style.org/, http://thesassway.com/beginner
