The design is based upon the colour schemes of the flags of the twenty seven member states.
What cannot be seen here is the fact that the colour scheme for the Finns was reversed. They were not amused.
The French blamed a Dutch contractor for the error, then when this was felt to be unacceptable as an excuse claimed that they had not seen the great bubble before it was blown up in situ.
I was of course late to this story
Many thanks to a new(ish) friend for these splendid pictures.