title: broccoli-sass, node-sass, breakpoint-sass
body: <p>I'm trying to use <code>breakpoint-sass</code> with <code>broccoli-sass</code> in my Ember CLI project, but when using <code>@include breakpoint(100px)</code> it crashes with the following error:</p>
  
  <pre><code>cannot add or subtract numbers with incompatible units
   [string exception]
  </code></pre>
  
  <p>It's simple to reproduce:</p>
  
  <pre><code># install latest version of ember-cli:
  $ npm install -g ember-cli
  
  # create a new app:
  $ ember new breakpoint-sass-test
  $ cd breakpoint-sass-test
  
  # add broccoli-sass
  $ npm install --save-dev broccoli-sass
  
  # install breakpoint:
  $ bower install breakpoint
  
  # add the following line to `Brocfile.js`:
  app.import('bower_components/breakpoint/breakpoint/_breakpoint.scss');
  
  # add the following lines to `app/styles/app.scss`: 
  @import "bower_components/breakpoint/breakpoint/_breakpoint.scss";
  
  .test {
    @include breakpoint(100px) {
      display:none;
    }
  }
  </code></pre>