* Align spinner buttons on right
The initial rationale for splitting them up was to be more touch friendly,
but we won't be able to use them on mobile anyway due to the conflicts
with double taps zooming in. On desktop, having them apart requires more
mouse movement when overshooting, so it's better to have them in one
place.
Text is now left-aligned again, which matches our other inputs like
learning steps.
The left/right buttons have been changed to up/down, which matches our
Qt spinners, and avoids RTL concerns.
This commit also removes the border on hover/select - it caused the
left-aligned content to flicker, and didn't look correct. Perhaps we could
add it back in a better way in the future.
* Hide spinner buttons on mobile devices
Tapping on them conflicts with the page zoom gesture.
* Remove min-height on spinner buttons
* Only show spinner on hover
Since they're only useful with a mouse, and only useful when they're
under the cursor, hiding them when focused keeps things less cluttered.
3d8c7f5ea1