Everything suddenly bold

Hi – after designing my site, I went back to it a couple of days ago to find all the text is suddenly now bold. It wasn’t like that before so I can only assume something has been jigged following an update? My tech knowledge is pretty limited so I don’t really know where to start looking, can anyone help me please? I am using Caeliora theme. Thank you.

The page I need help with: [log in to see the link]