Why do so many girls in Yr10 all of a sudden have red hair (literal)

Nope, saw several yr10s today who have dyed their hair red

Do ya happen to know why? I thought it might've been a trend that blew up on tiktok or something, but I don't know for sure because the clothing content I get shown is centred around... not UK fashion

Hi, so I'm in Year 10 and go to an all girls school, and recently I've noticed sooo many girls in my year group dye their hair red, like literal red, not ginger. It happened out of the blue?? If anyone knows why, because they've dyed their hair that red or something, please do tell? 'Chavs' and non-Chavs (idk what else to call them) are dying their hair this colour. It's really weird and it's been happening over the past week and I haven't asked any of them bc I don't know any of them like that. And yes this question has bugged me so much that this is my first post. Is it just my school???