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  // Loads the Flowbox Embed script
  (function(d, id) {
    if (!window.flowbox) { var f = function () { f.q.push(arguments); }; f.q = []; window.flowbox = f; }
    if (d.getElementById(id)) {return;}
    var s = d.createElement('script'), fjs = d.scripts[d.scripts.length - 1]; = id; s.async = true;
    s.src = '';
    fjs.parentNode.insertBefore(s, fjs);
  })(document, 'flowbox-js-embed');

<div class="tags">
  <button data-tag="fish" class="active">Fish</button>
  <button data-tag="meat">Meat</button>
  <button data-tag="vegetarian">Vegetarian</button>
  <button data-tag="burger">Burgers</button>

<div id="js-flowbox-flow"></div>
  // Initializes the Flowbox Embed into the #js-flowbox-flow div
  window.flowbox('init', {
    container: '#js-flowbox-flow',
    key: '00iOvX6IRjSQshRMTLAn7A',
    tags: ['fish']


                body {
  background: #333;
  padding-top: 40px;

.tags {
  display: flex;
  justify-content: center;
  margin-bottom: 50px;

button {
  background: #fafafa;
  border: none;
  border-bottom: 5px solid white;
  border-right: 1px solid #ccc;
  color: #333;
  cursor: pointer;
  display: inline-block;
  height: 50px;
  margin: 0;
  margin-bottom: 20px;
  outline: none;
  font-weight: bold;
  font-size: 17px;
  text-transform: uppercase;
  padding-bottom: 3px;
  letter-spacing: 0.5px;
} {
  border-bottom: 5px solid #0080ff;


 * Defines a function that takes a tag and updates the Flow
 * (using the same key as the script in our HTML code)
function updateFlow (tag) {
  window.flowbox('update', {
    key: '00iOvX6IRjSQshRMTLAn7A',
    tags: [tag],

// Gets all our buttons
const buttons = document.querySelectorAll('button[data-tag]')

// Function for looping through all buttons and clearing their classes
function clearButtonClasses () {
  for (const button of buttons) {

// Loops through all our buttons and adds click handlers
for (const button of buttons) {
  button.addEventListener('click', () => {
    // When clicking the button, use its data-tag attriibute to update the Flow