Html and CSS trying to focus on Cleaning up my CSS

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

I'm proud that I was able to make it a little responsive up to a certain point. I need to figure out how to make sure the card stays in the middle when It get to smaller screens.

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

Styling shadows still give me problems even with the figma file I had to use AI to get the syntax correct.Also I'm not sure if I'm doing responsiveness correct.

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

Any cratiques of my CSS organization is appreciated. I feel that the way I organizes things is fine for small projects but as soon as I have to scale up I feel I will get overwhelmed. Any Tip on how to order CSS? Right now I start putting things in order they are on the pages then after awhile just putting things anywhere. Also any tips on getting my pages to be actually responsive.