JSFiddle - React, Tailwind, and code Playground

HTML

<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.4/css/bootstrap.min.css">
<script src="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.4/js/bootstrap.min.js"></script>
<div class="row">
    <div class="col-md-12">
        <form action="" class="form-horizontal" id="newVehicle" method="post" accept-charset="utf-8">
            <div class="form-group">
                <label for="inputName" class="col-sm-2 control-label">Nome da viatura</label>
                <div class="col-sm-6">
                    <input type="text" class="form-control" name="name" id="inputName" placeholder="Nome da viatura">
                </div>
            </div>
            <div class="form-group specs" data-class="specs">
                <label for="" class="col-sm-2 control-label">Especificações</label>
                <div class="col-sm-4">
                    <select class="form-control" name="specs[]">
                        <option></option>
                        <option data-target="new-equip">Novo equipamento</option>
                    </select>
                </div>
                <div class="col-sm-2">
                    <div class="btn-group" role="group" aria-label=""> <a href="" class="btn btn-default btnNew"><span class="glyphicon glyphicon-pencil"></span></a>
 <a href="" class="btn btn-default btnPlus"><span class="glyphicon glyphicon-plus"></span></a>

                    </div>
                </div>
            </div>
            <div class="form-group equips" data-class="equips">
                <label for="" class="col-sm-2 control-label">Equipamento</label>
                <div class="col-sm-4">
                    <select class="form-control" name="equips[]">
                        <option></option>
                        <option data-target="new-equip">Novo equipamento</option>
                    </select>
                </div>
                <div class="col-sm-2">
                    <div class="btn-group" role="group"...

JavaScript

// IIFE - Immediately Invoked Function Expression
(function (yourcode) {

    // The global jQuery object is passed as a parameter
    yourcode(window.jQuery, window, document);

}(function ($, window, document) {

    // The $ is now locally scoped

    // Listen for the jQuery ready event on the document

    $(function () {

    });

    // The rest of the code goes here!


    $('#newVehicle').on('click', '.btnMinus, .btnNew, .btnPlus', function (event) {
        event.preventDefault();
        /* Act on the event */
        var formGroupClass = $(this).closest('.form-group').attr('data-class');
        console.log($(this).closest('.form-group').attr('class'));
        if ($(this).hasClass('btnMinus')) {
            if ($(this).closest('.form-group').is('.' + formGroupClass + ':first-child')) {
                return false;
            } else {
                $(this).closest('.form-group').remove();
            }
        }
        if ($(this).hasClass('btnPlus')) {
            $(this)
                .closest('.form-group')
                .after('<div class="form-group ' + formGroupClass + '" data-class="' + formGroupClass + '"></div>')
                .next()
                .append('<label for="" class="col-sm-2 control-label"></label>')
                .append('<div class="col-sm-4"></div>')
                .append('<div class="col-sm-2"></div>')
                .children('div.col-sm-4')
                .append('<select class="form-control" name="' + formGroupClass + '[]"></select>')
                .children('select')
                .append('<option></option>')
                .closest('.form-group')
                .children('div.col-sm-2')
                .append('<div class="btn-group" role="group" aria-label=""></div>')
                .children('.btn-group')
                .append('<a href="" class="btn btn-default btnMinus"><span class="glyphicon glyphicon-minus"></span></a>')
                .append('<a href="" class="btn btn-default...