- All of our red buttons were ImButton with the colours overridden at the
use site. Instead make an ImButtonRed which defines these colours in
one place.
- Previously the red buttons had focus indicated by the text colour
changing from white to blue. This was quite hard to see, instead
change the button colour to blue (as is done for the white buttons).
A darker shade of blue is used so that there is still good contrast
with the white text.
- Update the reds (buttons and main screen background) with the
branding-approved red: the official colour palette says Pi Red is
#cd2355
This change adjusts the layout for the progress bar, write button and
cancellation buttons such that they are all placed on the same layout
'row', with the progress bar stacked as before, and the
write/cancel/cancel buttons stacked as a column.
This is not ideal, but probably as sensible as we can get inside this
layout paradigm.