// folded box
@mixin folded ($size: 10px, $y: 30px, $background: $grey4) {
  line-height: $y;
  height: $y;
  margin-left: ($size * -1);
  text-indent: $size;
  position: relative;

  &:before {
    border-left: $size solid $pagebg;
    border-top: $size solid darken($background, 80%);
    float: left;
    content: '';
    position: absolute; 
    bottom: ($size * -1);
    left: 0;
  }
}