gistfile1.css

/*

    Less file 

*/
@width: 20px;
@color: orange;

.mixin { border: 1px solid black; }
.mixout { border-color: orange; }

#first > .one {
  #second .two > #deux {
    width: 50%;
    #third {
      color: @color;
      height: 100%;
    }
    #fourth, #fifth {
      color: red;
      .mixin > .inside;
    }
    .mixout;
  }
  font-size: 2em;
}

/*

    inspecting the tree (note the expanded selectors)

*/

*
.  @width: `20px`
.  @color: `orange`
.  .mixin
.  .  border: `1px solid black`
.  
.  .mixout
.  .  border-color: `orange`
.  
.  #first
.  .  .one
.  .  .  font-size: `2em`
.  .  .  #second
.  .  .  .  .two
.  .  .  .  .  #deux
.  .  .  .  .  .  width: `50%`
.  .  .  .  .  .  #third
.  .  .  .  .  .  .  color: `@color`
.  .  .  .  .  .  .  height: `100%`
.  .  .  .  .  .  
.  .  .  .  .  .  #fifth
.  .  .  .  .  .  .  color: `red`
.  .  .  .  .  .  .  .mixin
.  .  .  .  .  .  .  .  .inside
.  .  .  .  .  .  .  
.  .  .  .  .  .  
.  .  .  .  .  .  .mixout
.  .  .  .  .  
.  .  .  .  
.  .  .  
.  .  
.  

/* CSS Generated with Less 0.8.13 */

.mixin { border: 1px solid black; }
.mixout { border-color: orange; }
#first > .one { font-size: 2em; }
#first > .one #second .two > #deux { width: 50%; }
#first > .one #second .two > #deux #third {
  color: @color;
  height: 100%;
}
#first > .one #second .two > #deux #fifth { color: red; }