So you do not know what I mean when I say byline? OK. You are right that the bit you quoted does not mention the direction of the ball. Well done. If you do not know that the ball must be passed forward for anyone to be offside I can't help you.
What do you mean it doesn't matter? Of course it does. It is only offside if the ball goes forward. That's why wingers, in the old days, went to the byline and crossed the ball. Everyone was onside.