$Capital-letter: 1em;
$_Capital-letter: 1em;
$123-is-not-allowed: 1em;

$weird-stuff-!@#$*: 1em;


// nested selectors
.page-container {

  .content {

    .profile {

      .too-deep { }
    }
  }
}


// extend
.Card { }

.ListingCard {
  @extend .Card;
}


// order
@mixin border-radius($radius) {
  border-radius: $radius;
}

.box--red {
  @include border-radius(10px);
  top: 0;
}

.box--green {

  .content { }

  top: 0;
}

.box--red {
  @media print {
    background: white;
  }

  @include border-radius(10px);
}

.box--blue {

  .content { }

  @media print {
    background: white;
  }
}