.field-help-text {
  margin-top: -20px;
  margin-bottom: $baseline-unit*6;

  .js & {
    @include respond-to($mq-m) {
      position: absolute;
      margin-top: $baseline-unit*4;

      &.help-text--hidden {
        @include visually-hidden;
      }
    }
  }
}

.js .field-help-text--jshide {
  @include visually-hidden;
}

.field-help-text {
  margin-top: -20px;
  margin-bottom: $baseline-unit*6;

  .js & {
    @include respond-to($mq-m) {
      position: absolute;
      margin-top: $baseline-unit*4;

      &.field-help-text--hidden {
        @include visually-hidden;
      }
    }
  }
}

.js .field-help-text--jshide {
  @include visually-hidden;
}

Correct field text hidden class name
Correct field text hidden class name
