Easy

I cannot be felt, seen or touched; Yet I can be found in everybody; My existence is always in debate; Yet there is a style of music named after me.

Every country has one, though we are not the same. Waving to our citizens, throughout the wind and rain. What is it?

The day is their night and the night is their day, when I shout and they shout back I run away.

What hangs in the sky by day but at night goes away?

Riddles and Answers