No mixin named background

[wzup]

Error:

Module build failed:
undefined
                ^
      No mixin named background

And I've checked, there is indeed no background mixin in compass-mixins plugin. How can it be?

This is all the plugin offers:

@import "css3/background-clip";
@import "css3/background-origin";
@import "css3/background-size";
_grid-background.scss

And this is the mixin
http://compass-style.org/reference/compass/css3/images/#mixin-background

If any, I use your package in Webpack workflow. It is Webpack that throws the error.

[wzup]

Well, actually you have. But why it doesn't work?

Here it is, in this folder:
\compass-mixins\lib\compass\css3\_images.scss

This is how I use the mixin. Why loader cannot find it?

    .material-icon-custom {
        @include background(linear-gradient(white, #cccccc, #aaaaaa));
        @include background-clip(text);
        -webkit-text-fill-color: transparent;
    }