Following SASS:

Code:
.some-cls {
  &-over:before {
    content: '';
  }
}
will process following CSS:

Code:
.some-cls:before-over{
  content: '';
}
But it should be:


Code:
.some-cls-over:before{
  content: '';
}

Next link demonstrates right building CSS: https://www.sassmeister.com/gist/5a4...13056e5367c832

Used Sencha CMD 6.5.2.15