DayMode: improvements

[dennisguse]

Follow-up to #417.

• TrackController background needs a different background color
  But, the two buttons have a transparent background, so either we adjust those as well or we keep/use a darker background color.
• colorAccent: we use the orange from the logo and it could be a little bit darker in day mode.
  We could use the same color as Trail-Sense: Day / night mode #417 (comment)