I've been successfully using lsp-mode and magit for a while with a light theme (leuven).
Today I was messing with something seemingly unrelated (company-mode and auto-complete settings in my ~/.emacs file) and all of a sudden popups in lsp-mode + company-mode appear as if in a dark theme:

The same goes now in magit for the area where the cursor is:

Needless to say, it's all unreadable now!
How can I get the light colours back?
My ~/.emacs contents are here, if it helps: https://pastebin.com/Hph4VXvH
Thanks!