Improve homepage/navigation layout/design

[carlgao]

The current layout of the homepage emphasizes things that are not immediately relevant to users, such as Press. Indeed, only one of the tabs “Courses” is relatively important. We suggest changing the home page so that users can access the different universities directly from the home screen. Additionally, the design of the homepage might be improved with the following suggestions:
"a 501(c)(3)...open education project" could be at the top right corner. A subtext under that could be "Improving access to education, one lecture at a time."
“Random lecture!" should be a button off to the side or in the corner somewhere, rather than the most prominent home page button. It has novelty but not much utility, since most notes are for classes a regular student is not interested or invested in.
The sideways screenshots are not immediately distinguishable. They should be expanded and laid out flat. For aesthetics the screenshots could still largely overlap corners. (Also, can students really create blogs and geometric diagrams like that on the site?)
Use more cheerful colors. The dark color scheme does not entice users to explore the site further.