// prefix declarations
.prefixed(@property, @value) {
  & when (@webkit = true) {
    -webkit-@{property}: @value;
  }

  & when (@moz = true) {
      -moz-@{property}: @value;
  }

  & when (@ms = true) {
      -ms-@{property}: @value;
  }

  & when (@o = true) {
      -o-@{property}: @value;
  }

  @{property}: @value;
}

// prefix keyframes
.keyframes(@name; @content) {
  & when (@webkit = true) {
    @-webkit-keyframes @name {
      @content();
    }
  }

  & when (@moz = true) {
      @-moz-keyframes @name {
          @content();
      }
  }

  & when (@ms = true) {
      @-ms-keyframes @name {
          @content();
      }
  }

  & when (@o = true) {
      @-o-keyframes @name {
          @content();
      }
  }

  @keyframes @name {
    @content();
  }
}