refine footer component #56
Description
Spinoff from #52 again
The footer component has some very cute UI and responsivity thanks to #16. After we refactored the layout in #52, the footer styles are a bit delicate and some pages don't match their responsive design perfectly.
- i.e., in "story" page, if you add a border top to match the border bottom on header, you can see the width is broken
- also previously footer sometimes appears not on the bottom, and after i set a default layout, this behavior is gone, not sure how we can do this properly now