Photos from Unsplash, used under the Unsplash License (free to use, attribution appreciated).

hero.jpg: Pratik Mohapatra (https://unsplash.com/@sipunpratik), https://unsplash.com/photos/tK3YUyBmWqw
hands.jpg: Vitaly Gariev (https://unsplash.com/@silverkblack), https://unsplash.com/photos/hImHC7Posuo
discussion.jpg: Vitaly Gariev (https://unsplash.com/@silverkblack), https://unsplash.com/photos/wAgfqXpYqug
mics.jpg: A. C. (https://unsplash.com/@3tnik), https://unsplash.com/photos/NbF-3zGkjE4
classroom.jpg: Quilia (https://unsplash.com/@heyquilia), https://unsplash.com/photos/zFSo6bnZJTw
crowd.jpg: Abhinav Anand (https://unsplash.com/@infinitepov), https://unsplash.com/photos/ARD-rlIk2ig