JSFiddle - React, Tailwind, and code Playground

HTML

<script>
  var pbjs = pbjs || {};
  pbjs.que = pbjs.que || [];

  pbjs.que.push(function() {
    var adUnits = [{
      code: 'zone-1',
      sizes: [
        [300, 250]
      ],
      bids: [{
        bidder: 'mantis',
        sizes: [
          [300, 250]
        ],
        params: {
          property: 'demo'
        }
      }]
    }, {
      code: 'zone-2',
      sizes: [
        [728, 90]
      ],
      bids: [{
        bidder: 'mantis',
        sizes: [
          [728, 90]
        ],
        params: {
          property: 'demo'
        }
      }]
    }, {
      code: 'zone-3',
      sizes: [
        [320, 50]
      ],
      bids: [{
        bidder: 'mantis',
        sizes: [
          [320, 50]
        ],
        params: {
          property: 'demo'
        }
      }]
    }, {
      code: 'zone-4',
      sizes: [
        [300, 600]
      ],
      bids: [{
        bidder: 'mantis',
        sizes: [
          [300, 600]
        ],
        params: {
          property: 'demo'
        }
      }]
    }];

    pbjs.addAdUnits(adUnits);

    pbjs.requestBids({
      bidsBackHandler: function() {
        var params = pbjs.getAdserverTargeting();

        for (var id in params) {
          if (params[id] && params[id]['hb_adid']) {
          	var iframe = document.createElement('iframe');
            iframe.style.border = 0;
            
            document.getElementById(id).appendChild(iframe);
            
            pbjs.renderAd(iframe.contentWindow.document, params[id]['hb_adid']);
          } else {
            document.getElementById(id).innerHTML = 'No ads';
          }
        }
      }
    });
  });

</script>

<script type="text/javascript" src="https://mantis-test.s3.amazonaws.com/prebid/prebid.js" async></script>

<h2>Mantis Prebid.js Test</h2>

<h5>Zone-1</h5>
<div id='zone-1'></div>

<h5>Zone-2</h5>
<div id='zone-2'></div>

<h5>Zone-3</h5>
<div id='zone-3'></div>

<h5>Zone-4</h5>
<div id='zone-4'></div>