Atlantis theme: _colours.scss causing errors

[pgathercole]

Have recently purchased the Atlantis theme (6.0.0) and tried to run the Demo app with Primefaces 13.0.10 and it is generally absolutely fine except for one .scss file, _colours which complains about unexpected characters, mainly '-', and therefore breaks some other bits as well.

It seems as though it must be a simple problem but I have absolutely no idea what is is, so any solutions would be much appreciated.