Previously, the content width on the "Contributors" page (`/about`) and the "Cheat sheet" guide (`/guide/cheatsheet`) was unlimited (i.e. the content would take up all the available space horizontally). This was not very ergonomic on large screens. Especially on the "Cheat sheet" guide there was a lot of unnecessary whitespace between the code shown on the left column and the description shown on the right column. This commit fixes this by setting a max content width for both pages of 84em (1404px by default). This keeps the content at a more manageable width and avoids unnecessary whitespace. Before (contributors): ![contributors page on 2500px before][1] Before (cheatsheet): ![cheatsheet on 2500px before][2] After (contributors): ![contributors page on 2500px after][3] After (cheatsheet): ![cheatsheet on 2500px after][4] [1]: https://user-images.githubusercontent.com/8604205/109394323-1bb1e800-792f-11eb-9cd6-c5b83e5ae921.png [2]: https://user-images.githubusercontent.com/8604205/109394329-1fde0580-792f-11eb-91c0-4ed7ad408b17.png [3]: https://user-images.githubusercontent.com/8604205/109394319-181e6100-792f-11eb-9463-a281dfe80448.png [4]: https://user-images.githubusercontent.com/8604205/109394330-210f3280-792f-11eb-9837-ddc7a8d01d19.png PR Close #41051