Feedback on week2

Overall I saw great improvement and growth from week 2 project which is very good. I can see quite amount of improvement from our last 1-1
## Code Structure
From week 1, the code is more structured and put into reasonable directories.
Still, some unused .css files end up being pushed into the final repo. They should be excluded.
## Style
Pretty clean and tight.
Nit: Some inconsistent whitespacing, and code can be cleaner with certain choices. This is really not a convenient place to extend, will cover them during 1-1