Since this is an older theme and hasn't been updated in a while to run with node 21, python3.12 can you please provide the versions of Node, NPM and Python used to compile the sources?
You may try with Node v17.x - we use node sass for SASS compile and you may check out here more information about versioning for Node https://github.com/sass/node-sass
Node, NPM, Python versions needed
You may try with Node v17.x - we use node sass for SASS compile and you may check out here more information about versioning for Node https://github.com/sass/node-sass
Hope that helps!
Thanks again!