Dash to dock installation error on debian 12

Hello, I am new, as a newbie I struggle at every corner :)
I am trying to add dash to dock extension to gnome.
I found those instructions :
git clone https://github.com/ewlsh/dash-to-dock/
cd dash-to-dock
git checkout ewlsh/gnome-40
make
make install
At "make" step I get this error :
sassc --omit-map-comment _stylesheet.scss stylesheet.css
make: sassc: No such file or directory
make: *** [Makefile:66: stylesheet.css] Error 127

I don't know how to solve that.
Would you have an idea ? Please :)
Thank you in advance