SourceMap points to wrong source file in Sass?

Question

Sass

There is a task in Gulp for compiling sass, there is one main file main.sass, libraries are imported in it at the very beginning (in particular, I connected Bulma), then variables, fonts, and so on. The most recent import is the _base.sass file, where I want to write basic styles, for example

a
  color : green

After compilation, I want to check the correctness of the sourcemap processing in chrome, and they point me to the generic.sass source file, this file belongs to Bulma, it also has such a line but through a variable

a
    color: $link-color

The question is why does it point to it if I write my styles already after this file in the structure hierarchy, and write any other color for links in my file and still refer to the Bulma file. If I prescribe the color of the link through the class, then the sourcemap works fine.