update sass to latest version

[volarname]

there are several deprecations in sass

Global built-in functions are deprecated and will be removed in Dart Sass 3.0.0.
Use meta.function-exists instead.

Sass @import rules are deprecated and will be removed in Dart Sass 3.0.0.

and more

please update source code to latest supported sass

[volarname]

i see a PR to switch to sass and node 20
#28
this issue is linked, first that update is needed and then surce code can be updated to remove deprecated syntax