People have been sharing photos of themselves putting their foot on their arm for a "challenge" that has gone viral on Weibo, China's biggest social network.
It all started after a Weibo user shared screenshots from the anime Case Closed, in which the main character — Detective Conan — says the length of one's foot is the same as the length of one's forearm.
"Thank you Conan, for expanding my knowledge."
People immediately tried it out.
