Focus on first input field

Hi

  How to set focus on first input field without Javacript when Modal Popup opens

<div class="form-group row">
                                    <label class="control-label col-sm-3" for="Id">Id</label>
                                    <div class="col-sm-9">
                                        <input type="text" class="form-control form-control-sm"  id="txtId" name="Id" placeholder="Id">
                                    </div>
                                </div>

Thanks