JSFiddle - React, Tailwind, and code Playground

HTML

<script src="http://ajax.googleapis.com/ajax/libs/angularjs/1.4.8/angular.min.js"></script>
<link rel="stylesheet" href="http://www.w3schools.com/lib/w3.css">


<script>
var app = angular.module("myTodayList", []);
app.controller("myCtrl", function($scope, $http) {
    $scope.products = ["Leeana", "Site", "Teeeyoma"];
    $scope.addItem = function () {
        $scope.errortext = "";
        if (!$scope.addMe) {return;}
        if ($scope.products.indexOf($scope.addMe) == -1) {
            $scope.products.push($scope.addMe);
        } else {
            $scope.errortext = "The item is already in your today list.";
        }
    }
    $scope.removeItem = function (x) {
        $scope.errortext = "";
        $scope.products.splice(x, 1);
    }
});
</script>

{%verbatim%}
<div ng-app="myTodayList" ng-cloak ng-controller="myCtrl" class="w3-card-2 w3-margin" style="max-width:400px;">
  <header class="w3-container w3-light-grey w3-padding-16">
    <h3>My today list</h3>
  </header>
  <ul class="w3-ul">
    <li ng-repeat="x in products" class="w3-padding-16">{{x}}<span ng-click="removeItem($index)" style="cursor:pointer;" class="w3-right w3-margin-right">Ă—</span></li>
  </ul>
  <div class="w3-container w3-light-grey w3-padding-16">
    <div class="w3-row w3-margin-top">
      <form id="new_thingtodo_form">
          <div class="w3-col s10">
              <input placeholder="Add your tasks here" ng-model="addMe" class="w3-input w3-border w3-padding" id="thingtodo">
          </div>
          <div class="w3-col s2">
              <input ng-click="addItem()" class="w3-btn w3-padding w3-green" type="submit" value="Add">
          </div>
      </form>
    </div>
  </div>
    <p class="w3-padding-left w3-text-red">{{errortext}}</p>
</div>
{%endverbatim%}


<script>
$(document).on('submit','#new_thingtodo_form', function(e) {
    e.preventDefault();

    $.ajax({
        type: 'POST',
        url: '/today/',
        data: {
            thingtodo: $('#thingtodo'), val()
       ...