Not a spoiler, but a cultural thing you wouldn't know:

You'll notice that Zhao Yun Lan's hairstyle changed between episodes 14 and 15. I can't find the exact quote, but when Bai Yu (the actor) was asked about it, he said something like, that's what you do when you make an important change in your life.

What he meant was *marriage*. It's traditional for Chinese women to change their hairstyle when they get married, so you have "before" hair and "after" or "bride" hair.

Bride Hair. There you have it.