Great job on your CSS! I really appreciate how you've utilized variables, making the code clean and customizable. The consistent naming conventions and thoughtful use of media queries for responsiveness is also well done. I also like the fact that you included a CSS reset.
I'm currently focusing on honing my skills, and while I'm not yet confident enough to provide constructive criticism, I genuinely appreciate the opportunity to learn from your work. Thank you for sharing, and best of luck with your future projects!