first > .one {

> #second .two > #deux {
  width: 50%;
  #third {
    &:focus {
      color: black;
      #fifth {
        > #sixth {
          .seventh #eighth {
            + #ninth {
              color: purple;
            }
          }
        }
      }
    }
    height: 100%;
  }
  #fourth, #five, #six {
    color: #110000;
    .seven, .eight > #nine {
      border: 1px solid black;
    }
    #ten {
      color: red;
    }
  }
}
font-size: 2em;

}