Generated by SassMeister.com.

SassMeister-input.scss

// ----
// libsass (v3.2.5)
// ----

@mixin my-mixin($color){
  background: $color;
  outline: 3px solid red;
  padding: 12px;
  margin: 24px;
}
%my-mixin{
  background: red;
  outline: 3px solid red;
  padding: 12px;
  margin: 24px;
}
//
// using mixin
//
.class-one{
  @include my-mixin(red);
}
.another-two {
  @include my-mixin(red)
}
//
// using extend
//
.class-three{
  @extend %my-mixin;
}
.class-four {
  @extend %my-mixin; 
}
.class-five .class-six {
  @extend %my-mixin;
}

SassMeister-output.css

.class-three, .class-four, .class-five .class-six {
  background: red;
  outline: 3px solid red;
  padding: 12px;
  margin: 24px; }

.class-one {
  background: red;
  outline: 3px solid red;
  padding: 12px;
  margin: 24px; }

.another-two {
  background: red;
  outline: 3px solid red;
  padding: 12px;
  margin: 24px; }