Hello Andrew,
I just installed the new lessframwork.css in the kabuki theme folder. It seems to have not resloved the problem but actually made it worse. The main menu is now totally missing when visting the site from a mobile phone. I backed up the previous framework.css so everything should be ok. I noticed when going to the kabuki heme preview on themeforest: https://satoristudio.net/themedemo/?theme=kabuki on a mobile it seems to work fine in regards to the resposivness not reverting to a mobile theme.
Cheers.
– Mike