Why won't my Datamaps plugin show up on my Tumblr blog page?

Question

Trying to install datamaps plugin onto Tumblr blog page, map won't show up

I'm a beginner to coding, and have been trying to install an interactive political on a page of my tumblr; I have received permission from Support to run Javascript on my blog. I've been following the documentation on the Github and put the following code on page:

<script src="//cdnjs.cloudflare.com/ajax/libs/d3/3.5.3/d3.min.js"></script>
<script src="//cdnjs.cloudflare.com/ajax/libs/topojson/1.6.9/topojson.min.js"></script>
<script src="/datamaps.world.min.js"></script>
<div id="container" style="position: relative; width: 500px; height: 300px;"></div>
<script>
    var map = new Datamap({element: document.getElementById('container')});
</script>

However, nothing shows up when I hit the preview button. Using inspect, the container is present but the map is not.