JSFiddle - React, Tailwind, and code Playground

HTML

<script src="//code.jquery.com/jquery-1.12.0.min.js"></script>
<script src="//code.jquery.com/jquery-migrate-1.2.1.min.js"></script>
           <div class="box box-warning">
                <div class="box-header with-border">
                  <h3 class="box-title">Dane do faktury</h3>
                </div><!-- /.box-header -->
                  <div class="box-body">
                      <button id="b1" class="btn add-more add_field_button" type="button">Dodaj pole</button>
                    <form>
                        <div id="field" class="input_fields_wrap">
                            <div>
                                <div class="col-xs-8">
                                  <input type="text" name="element[]" class="form-control" placeholder="Element">
                                </div>
                                <div class="col-xs-3">
                                  <input type="text" name="price[]" class="form-control" placeholder="Cena">
                                </div>
                                <hr>
                            </div>
                        </div>
                        
                    </form>
                      
                  </div><!-- /.box-body -->
              </div><!-- /.box -->

CSS

@import url(https://fonts.googleapis.com/css?family=Source+Sans+Pro:300,400,600,700,300italic,400italic,600italic);html,body{min-height:100%}.layout-boxed html,.layout-boxed body{height:100%}body{-webkit-font-smoothing:antialiased;-moz-osx-font-smoothing:grayscale;font-family:'Source Sans Pro','Helvetica Neue',Helvetica,Arial,sans-serif;font-weight:400;overflow-x:hidden;overflow-y:auto}.wrapper{min-height:100%;position:static;overflow:hidden}.wrapper:before,.wrapper:after{content:" ";display:table}.wrapper:after{clear:both}.layout-boxed .wrapper{max-width:1250px;margin:0 auto;min-height:100%;box-shadow:0 0 8px rgba(0,0,0,0.5);position:relative}.layout-boxed{background:url('../img/boxed-bg.jpg') repeat fixed}.content-wrapper,.right-side,.main-footer{-webkit-transition:-webkit-transform .3s ease-in-out,margin .3s ease-in-out;-moz-transition:-moz-transform .3s ease-in-out,margin .3s ease-in-out;-o-transition:-o-transform .3s ease-in-out,margin .3s ease-in-out;transition:transform .3s ease-in-out,margin .3s ease-in-out;margin-left:230px;z-index:820}.layout-top-nav .content-wrapper,.layout-top-nav .right-side,.layout-top-nav .main-footer{margin-left:0}@media (max-width:767px){.content-wrapper,.right-side,.main-footer{margin-left:0}}@media (min-width:768px){.sidebar-collapse .content-wrapper,.sidebar-collapse .right-side,.sidebar-collapse .main-footer{margin-left:0}}@media (max-width:767px){.sidebar-open .content-wrapper,.sidebar-open .right-side,.sidebar-open .main-footer{-webkit-transform:translate(230px, 0);-ms-transform:translate(230px, 0);-o-transform:translate(230px, 0);transform:translate(230px, 0)}}.content-wrapper,.right-side{min-height:100%;background-color:#ecf0f5;z-index:800}.main-footer{background:#fff;padding:15px;color:#444;border-top:1px solid #d2d6de}.fixed .main-header,.fixed .main-sidebar,.fixed .left-side{position:fixed}.fixed .main-header{top:0;right:0;left:0}.fixed .content-wrapper,.fixed .right-side{padding-top:50px}@media...

JavaScript

var max_fields      = 10;
    var wrapper         = $(".input_fields_wrap");
    var add_button      = $(".add_field_button");
    
    var x = 1; //initlal text box count
    $(add_button).click(function(e){ //on add input button click
        e.preventDefault();
        if(x < max_fields){ //max input box allowed
            x++; //text box increment
            $(wrapper).append('<div><div class="col-xs-8"><input type="text" name="element[]" class="form-control" placeholder="Element"></div><div class="col-xs-3"><input type="text" name="price[]" class="form-control" placeholder="Cena"></div><div class="col-xs-1"><a href="#" class="remove_field">Usuń</a></div>'); //add input box
        }
    });
    
    $(wrapper).on("click",".remove_field", function(e){ //user click on remove text
        e.preventDefault(); $(this).parent('div').remove(); x--;
    });