Streamgraph extent under cursor

<!DOCTYPE html>
<meta charset="utf-8">
<style>

body {
  font: 10px sans-serif;
}

.chart { 
  background: #fff;
}

p {
  font: 12px helvetica;
}

.axis path, .axis line {
  fill: none;
  stroke: #000;
  stroke-width: 2px;
  shape-rendering: crispEdges;
}

button {
  position: absolute;
  right: 50px;
  top: 10px;
}

</style>
<body>
<script src="https://d3js.org/d3.v3.min.js"></script>

chart("data.csv", "orange");

var datearray = [];
var colorrange = [];

function chart(csvpath, color) {

if (color == "blue") {
  colorrange = ["#045A8D", "#2B8CBE", "#74A9CF", "#A6BDDB", "#D0D1E6", "#F1EEF6"];
}
else if (color == "pink") {
  colorrange = ["#980043", "#DD1C77", "#DF65B0", "#C994C7", "#D4B9DA", "#F1EEF6"];
}
else if (color == "orange") {
  colorrange = ["#B30000", "#E34A33", "#FC8D59", "#FDBB84", "#FDD49E", "#FEF0D9"];
}
strokecolor = colorrange[0];

var format = d3.time.format("%m/%d/%y");

var margin = {top: 20, right: 40, bottom: 30, left: 30};
var width = document.body.clientWidth - margin.left - margin.right;
var height = 400 - margin.top - margin.bottom;

var tooltip = d3.select("body")
    .append("div")
    .attr("class", "remove")
    .style("position", "absolute")
    .style("z-index", "20")
    .style("visibility", "hidden")
    .style("top", "330px")
    .style("left", "45px");

var x = d3.time.scale()
    .range([0, width]);

var y = d3.scale.linear()
    .range([height-10, 0]);

var z = d3.scale.ordinal()
    .range(colorrange);

var xAxis = d3.svg.axis()
    .scale(x)
    .orient("bottom")
    .ticks(d3.time.weeks);

var yAxis = d3.svg.axis()
    .scale(y);

var yAxisr = d3.svg.axis()
    .scale(y);

var stack = d3.layout.stack()
    .offset("silhouette")
    .values(function(d) { return d.values; })
    .x(function(d) { return d.date; })
    .y(function(d) { return d.value; });

var nest = d3.nest()
    .key(function(d) { return d.key; });

var area = d3.svg.area()
    .interpolate("cardinal")
    .x(function(d) { return x(d.date); })
    .y0(function(d) { return y(d.y0); })
    .y1(function(d) { return y(d.y0 + d.y); });

var svg = d3.select(".chart").append("svg")
    .attr("width", width + margin.left + margin.right)
    .attr("height", height + margin.top + margin.bottom)
  .append("g")
    .attr("transform", "translate(" + margin.left + "," + margin.top + ")");

var graph = d3.csv(csvpath, function(data) {
  data.forEach(function(d) {
    d.date = format.parse(d.date);
    d.value = +d.value;
  });

var layers = stack(nest.entries(data));

x.domain(d3.extent(data, function(d) { return d.date; }));
  y.domain([0, d3.max(data, function(d) { return d.y0 + d.y; })]);

svg.selectAll(".layer")
      .data(layers)
    .enter().append("path")
      .attr("class", "layer")
      .attr("d", function(d) { return area(d.values); })
      .style("fill", function(d, i) { return z(i); });

svg.append("g")
      .attr("class", "x axis")
      .attr("transform", "translate(0," + height + ")")
      .call(xAxis);

svg.append("g")
      .attr("class", "y axis")
      .attr("transform", "translate(" + width + ", 0)")
      .call(yAxis.orient("right"));

svg.append("g")
      .attr("class", "y axis")
      .call(yAxis.orient("left"));

var axisExtentLine = svg.append("line")
      .attr({"class": "extent", "stroke-width": 5, "stroke-opacity": 0.8, stroke: "red", "pointer-events": "none"});

var cursorExtentLine = svg.append("line")
      .attr({"class": "extent", "stroke-width": 3, "stroke-opacity": 0.8, stroke: "white", "pointer-events": "none"});

svg.selectAll(".layer")
    .attr("opacity", 1)
    .on("mouseover", function(d, i) {
      svg.selectAll(".layer").transition()
      .duration(250)
      .attr("opacity", function(d, j) {
        return j != i ? 0.6 : 1;
    })})

.on("mousemove", function(d, i) {
      mouse = d3.mouse(this);
      mousex = mouse[0];
      var invertedx = x.invert(mousex);
      invertedx = invertedx.getMonth() + invertedx.getDate();
      var selected = (d.values);
      for (var k = 0; k < selected.length; k++) {
        datearray[k] = selected[k].date
        datearray[k] = datearray[k].getMonth() + datearray[k].getDate();
      }

mousedate = datearray.indexOf(invertedx);
      var currentValue = d.values[mousedate];
      pro = currentValue.value;
      var posY = currentValue.y0;
      var posX = x(currentValue.date);

axisExtentLine.attr({x1: 0, y1: y(pro), x2: 0, y2: height -10 });
      cursorExtentLine.attr({x1: posX, y1: y(pro) - (height - y(posY) - 10), x2: posX, y2: height  - (height - y(posY)) });

d3.select(this)
      .classed("hover", true)
      .attr("stroke", strokecolor)
      .attr("stroke-width", "0.5px"), 
      tooltip.html( "<p>" + d.key + "<br>" + pro + "</p>" ).style("visibility", "visible");
      
    })
    .on("mouseout", function(d, i) {
     svg.selectAll(".layer")
      .transition()
      .duration(250)
      .attr("opacity", "1");
      d3.select(this)
      .classed("hover", false)
      .attr("stroke-width", "0px"), tooltip.html( "<p>" + d.key + "<br>" + pro + "</p>" ).style("visibility", "hidden");
  })
    
  var vertical = d3.select(".chart")
        .append("div")
        .attr("class", "remove")
        .style("position", "absolute")
        .style("z-index", "19")
        .style("width", "1px")
        .style("height", "380px")
        .style("top", "10px")
        .style("bottom", "30px")
        .style("left", "0px")
        .style("background", "#fff");

d3.select(".chart")
      .on("mousemove", function(){  
         mousex = d3.mouse(this);
         mousex = mousex[0] + 5;
         vertical.style("left", mousex + "px" )})
      .on("mouseover", function(){  
         mousex = d3.mouse(this);
         mousex = mousex[0] + 5;
         vertical.style("left", mousex + "px")});
});
}
</script>

Modified http://d3js.org/d3.v3.min.js to a secure url

https://d3js.org/d3.v3.min.js