Space Tourism React App

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

I learned react router and hash router from this project.

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

Most of the challenges are related to the cascading stylesheet. IMO, it took too much time for me.

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

I have finished 4 projects, but I think my responsive design skills are not improving. Please give me some recommendations/suggestions regarding to the responsiveness.