Use a monospace font for countdown #18
Description
Is your feature request related to a problem? Please describe.
The digits "jump around" when changing as we're currently using a variable-width font for them. This is especially annoying as due to the centered text, whenever a digit reaches 1 (i.e., at least every 10 seconds), the second digits jump horizontally by a few pixels.
Describe the solution you'd like
Use a monospaced font for the digits
Describe alternatives you've considered
One alternative might be to align the digits inside the boxes to the left (still somewhat centered, but text-aligned left) to avoid so much jumping, but that's far from ideal.
Additional context
GIF: https://i.imgur.com/2t5eBYH.gifv
