Set user contribution calendar `overflow-x: scroll` more precisely
This MR addresses two problems with the user contribution calendar container element:
- The horizontal scroll bar is initialized before it's needed
- When the scrollbar is initialized, you can't easily tell it's a scrollbar
I think setting a more precise viewport width to apply overflow-x: scroll addresses both pretty well. Generally it's a good idea to re-use viewport width variables, but IMO the fact that width of the user contribution calendar is hardcoded necessitates hardcoding the scrolling of its parent element.
Before
After
