Why is Sass ignoring my overrides?

Question

Sass

I want to override Bootstrap variables in Sass.
Here is my _variables.scss file:

@import "node_modules/bootstrap-sass/assets/stylesheets/bootstrap/variables";

// Brands
$brand-primary: #3097D1;

// Typography
$icon-font-path: "~bootstrap-sass/assets/fonts/bootstrap/";

// Container sizes
$container-large-desktop: (940px + $grid-gutter-width);

// Navbar
$navbar-default-bg: #fff;

Application main file:

// Variables
@import "variables";

// Bootstrap
@import "node_modules/bootstrap-sass/assets/stylesheets/bootstrap";

But, the container's size does not change. That is, the $container-large-desktop variable does not work. What's wrong? The rest of the variables override normally.