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                <div id="module">
  <pre class="javascript"><code>$(function(){

  /*** init variables ***/

  // just a bucket of things
  var things = [
    { module: 'sky', label: 'the sky'},
    { module: 'bell', label: 'a bell'},
    { module: 'bilboquet', label: 'a bilboquet' },
    { module: 'apple', label: 'an apple'},
    { module: 'hat', label: 'a hat' },
    { module: 'javascript', label: 'a javascript' },
    { module: 'rooster', label: 'a rooster' }

  var $sections = $('section');

  // keep track of each window/label used
  var usedGoods = [];
  var randomCorrectWindowId = Math.floor(Math.random() * 4);

  /*** helper functions ***/

  // returns id of object not yet used
  var generateRandomThing = function() {
    var usableId;
    var need = true;

    while ( need ) {
      usableId = Math.floor(Math.random() * things.length);

      // if x is not in usedGoods, set need to false and set as used
      if ( usedGoods.indexOf(usableId) === -1 ) {
        need = false;

    return usableId;

  /*** let's generate some friggin art ***/

  // for each section
    // generate random window and label to use
    var windowId = generateRandomThing();
    var labelId;

    // if random correct window, label and window IDs are the same
    if ( i === randomCorrectWindowId ) {
      labelId = windowId;
    else {
      labelId = generateRandomThing();

    // embed iframe of corresponding module
    var $iframe = $('&lt;iframe>');
      'src': ''+ things[windowId].module+'.html',
      'scrolling': 'no'

    // set text for this section's window
    $(this).find('.label').text( things[labelId].label);



                body { margin: 0; padding: 0; color: lime; background: black; }
#module { width: 100%; height: 200px; position: relative; overflow: hidden; }

@-webkit-keyframes javascript {
	0% {margin-top: 0px;}
	100% {margin-top: -800px;}
@-moz-keyframes javascript {
	0% {margin-top: 0px;}
	100% {margin-top: -800px;}

.javascript { position: absolute; 
  -webkit-animation: javascript 15s linear infinite; 
  -moz-animation:  javascript 15s linear infinite; 
  animation: javascript 15s linear infinite;