Allow to write css class inside an other class (like less)

[YglesEyes]

Hi all,
I open an issue on this subject because I didn't find it but perhaps I missed it...

It should be nice if we can write CSS class inside an other class like LESS manage it.

For example:

#card {
  background: red;
}
#card.disable {
  background: grey;
  color: black;
}

become:

#card {
  background: red;

  .disable {
    background: grey;
    color: black;
  }
}

[tabatkins]

You'll love the new CSS Nesting module, then. ^_^