Why does SASS compile to IBM866 encoding?

Question

Ruby on Rails

I set up the project through Grunt, but for some reason SASS began to add DOS encoding instead of UTF-8 in the final CSS; All .scss files are in UTF-8. config.rb
@charset "IBM866";

css_dir = "css"
sass_dir = "_/components/sass"
javascripts_dir = "js"
output_style = :compressed

Answer 1

config.rb

...
Encoding.default_external = "UTF-8"
....

OR
xxxx.scss

@charset "UTF-8";
...

something wrong with locales
sass-lang.com/documentation/file.SASS_REFERENCE.ht...