Change the colour of the Google Apps top menu background


I hate the default colour of the Inbox background on the top menu and it is so ugly compared to Stations UI

Wavebox allowed you to change the colour of the background with some CSS that you inserted into the accounts custom css area.

Can this be done with Station, the UI for Station is lovely, it’s a pity we can’t customise the Google apps background colour to fit in with the UI of Station

Thanks in advance