New to Kakoune, issues with themes and fzf

One more question: How do I change the colour of the flag in the status line? Like the one that goes [scratch] or [+] (according to this thread it’s supposedly called “flag”: Some questions about scratch buffer on pre-packaged Arch kak). It has the same background color as StatusLineMode yet still uses the foreground color of StatusLine which makes for a pretty unpleasant and barely readable combo.