gistfile1.scss

// A feature in Sass 3.2 (bleeding edge gem for now) is the concept of silent extends as follows
// By replacing the (.) with a (%), this will create a 'silent class' that is not written out to CSS
// until it is 'extended', EPIC!
// Put that in your OOCSS!

%kung {
  background: green;
  color: yellow;
}

%foo {
  background: orange;
  color: red;
  font-size: 12px;
}

.foo_one {
  @extend %foo;
}

.foo_two {
  @extend %foo;
}