Toilet seat fun!

Hi all

Hoping you can help, I’m losing the fight with a toilet seat. I’ve just recently moved into a new place, and the previous owners had Miomare (more like nightmare) family toilet seats for the little ones. I’ve spent all evening trying to work out how this toilet seat comes out. The identical one in another toilet was fine as that had a bolt underneath to remove it. However in this toilet you can’t get underneath to the bolt due to its design. I have no idea how they screwed it on and google has been little help. The only thing I can find about this toilet seat is the instructions for installing it which pretty much confirms it should have been screwed underneath. I see no quick release, no nuts or bolts and I can’t lift or move anything. Any ideas?