I’m developing a front in drupal with scss and bootstrap.

I get a compilation error

   error scss/inzicht_theme_tweaks/inzicht.scss (Line 144: Undefined mixin 'breakpoint'.) 

The code part

  @include breakpoint($  tablet) {         margin-left: 0px;         margin-right:0px;     } 

My main file is style.scss which looks like:

@import 'breakpoint';  // Default variables. @import "default-variables";  // Bootstrap Framework. @import '../bootstrap/assets/stylesheets/bootstrap';  // Base-theme overrides. @import 'overrides';  @import "inzicht_theme_tweaks/*";  @import "fontawesome/font-awesome"; 

The breakpoint is absoluut a partial.

07-12-2016  22:03    <DIR>          breakpoint 06-11-2017  21:28    <DIR>          component 08-11-2017  20:45    <DIR>          fontawesome 07-11-2017  11:13    <DIR>          inzicht_theme_tweaks 06-11-2017  21:28    <DIR>          jquery-ui 22-10-2017  08:24                20 layout.scss 10-11-2017  22:55               272 style.scss 10-11-2017  21:31             2.631 _breakpoint.scss 09-11-2017  19:47               639 _default-variables.scss 25-09-2017  17:34             1.254 _overrides.scss 

The breakpoint mixin is in _breakpoint.scss. But still it is not compiled well. I looked at several q/a questions but could not found the solution.

How to solve this?