Site builds outside of atom, but not in atom (File to import not found or unreadable)

[cryobry]

My site builds without any errors using the same command (bundle exec jekyll build) outside of atom, but the automatic build on save is returning:

jekyll 3.8.3 | Error: File to import not found or unreadable: normalize. on line 2

That line refers to my main.css file:

---
---

// "Reset" styles and SCSS reusable components
@import "normalize";
@import "mixins";
@import "variables";

// Generic site base & layout styles
@import "base";
@import "layout";

// Layouts
@import "resume";`

My _config.yml contains:

`sass:
  sass_dir: _sass
  style: compressed

And the _sass directory contains the necessary _normalize.css file.

When I comment out the @import "normalize"; line, I get the same error referring to the mixins import.