warnings using theme on i3

[CNote1]

Hi there, I'm having following issues using sweet dark theme on i3 wm:

(gnucash:55625): Gtk-WARNING **: 13:24:52.420: Theme parsing error: gtk-dark.css:5822:26: '-shadow' is not a valid color name

(gnucash:55625): Gtk-WARNING **: 13:24:52.423: Theme parsing error: gtk-dark.css:5825:14: not a number

(gnucash:55625): Gtk-WARNING **: 13:24:52.423: Theme parsing error: gtk-dark.css:5826:13: not a number

(gnucash:55625): Gtk-WARNING **: 13:24:52.423: Theme parsing error: gtk-dark.css:5827:11: Expected a length