Semantic HTML | Responsive Design

What are you most proud of, and what would you do differently next time?

I think I've managed to divide my css into biteable sections for more effective work. Also, I wanted to keep my code as dry as possible. Don't really know if it's dry though.

Next time I would think twice about my HTML structure, so that I don't need to re-structure it while styling the page.

What challenges did you encounter, and how did you overcome them?

There was a challenge with the structure of my HTML that had impact on my CSS work flow. And I guess I need to think about it beforehand next time, cause if it was a bigger project, I would be screwed.

What specific areas of your project would you like help with?

Any advice is welcome. HTML structure, CSS-related stuff, like dividing into modules, variables, anything. Thank you;)