Japanese Wedding Gift Money

(Edit the amount from 15万円to 15,000円, my bad!)

Hi! How much I should give to a friend's wedding? We used to be close but nowadays because of work and stuff we only hang out like once a year or at most twice. My friend is getting married to a Japanese person and they will have a shinto ceremony and a small reception after. Is 15,000 yen too little?

She said it is okay and I can just come empty handed but I am conflicted because I am worried her Japanese in laws might try to say things to her… Also should I adhere to a strict Japanese wedding's dress code? (This I can just ask her but lol).

by BlockMaster42