Another example for displaying GEONExT

<link rel="stylesheet" type="text/css" href="//jsxgraph.org/distrib/jsxgraph.css" />
<script type="text/javascript" src="//jsxgraph.org/distrib/jsxgraphcore.js"></script>
<script type="text/javascript" src="//jsxgraph.org/distrib/geonext.min.js"></script>
<div id="box" class="jxgbox" style="width:500px; height:500px;"></div>
<script type="text/javascript">
  var brd = JXG.JSXGraph.loadBoardFromFile('box', '//jsxgraph.org/geonext/Unendlich.gxt', 'Geonext');
</script>