Board Game Arena

As with many of these games, there is a variation. I can’t find it in the rules though. What’s the variation? Thanks

It's on the last page of the rules (on the English version at least)

Yes the rules say how to play, but how do you score the variant when going for number bonus?
Since there is all 3s in the middle star,
do you need just one inside (and all other stars with 3s filled) or all of them?