guided genes!!!

<!DOCTYPE html>
<head>
  <meta charset="utf-8">
  <script src="https://d3js.org/d3.v4.min.js"></script>
  <style>
    body { margin:0;position:fixed;top:0;right:0;bottom:0;left:0; }
  </style>
</head>

<body>
 
  <script>
    // Feel free to change or delete any of the code you see in this editor!
    var svg = d3.select("body").append("svg")
      .attr("width", 960)
      .attr("height", 500)

d3.json("data.json", function(err, mydata) {
        //if (err != null){console.log("whoopsie!")}
        //console.log(mydata);
       d3.select("svg").selectAll("rect")
        .data(mydata)
       	.enter()
       	.append("rect")
        .attr("y", 100)
        .attr("height", 50)
       	.attr("x", function(d){
         return d.start;
       })
        .attr("width", function (d){
         return d.stop-d.start;});
        .attr("fill", function(d) {
          if (d.orientation == "forward"){
            return "green";
          }
          else if (d.orientation == "reverse"{
            return "red";
                   })
          
          
        });
})

</script>
</body>

https://d3js.org/d3.v4.min.js