Adjustements on Markers scenario (now displays a "teacher" markers row) + Added a new "markers_teacher" scenario to edit the teacher markers and browse user markers

// Labels

.label-variant(@color) {
  background-color: @color;

  &[href] {
    &:hover,
    &:focus {
      background-color: darken(@color, 10%);
    }
  }
}