            <label class="form-control-label" for="inputInvalid">Invalid input</label>
            <input type="text" value="wrong value" class="form-control is-invalid" id="inputInvalid">
            <div class="invalid-feedback">Sorry, that username's taken. Try another?</div>
          </div>

          <div class="form-group">
            <label class="col-form-label col-form-label-lg" for="inputLarge">Large input</label>
            <input class="form-control form-control-lg" type="text" placeholder=".