[Solved]-How to make bar chart with additional vertical lines below the x axis-d3.js

var margin = {
    top: 20,
    right: 20,
    bottom: 60,
    left: 40
  },
  width = 560 - margin.left - margin.right,
  height = 360 - margin.top - margin.bottom;
var color = {
  Mechanical: '#4A7B9D',
  Electrical: '#54577C',
  Hydraulic: '#ED6A5A'
};
var barPadding = 40;
var data = [{
  key: 'Mechanical',
  values: [{
    key: 'Gear',
    value: 11
  }, {
    key: 'Bearing',
    value: 8
  }, {
    key: 'Motor',
    value: 3
  }]
}, {
  key: 'Electrical',
  values: [{
    key: 'Switch',
    value: 19
  }, {
    key: 'Plug',
    value: 12
  }, {
    key: 'Cord',
    value: 11
  }, {
    key: 'Fuse',
    value: 3
  }, {
    key: 'Bulb',
    value: 2
  }]
}, {
  key: 'Hydraulic',
  values: [{
    key: 'Pump',
    value: 4
  }, {
    key: 'Leak',
    value: 3
  }, {
    key: 'Seals',
    value: 1
  }]
}];
var rangeBands = [];
var cummulative = 0;
data.forEach(function(val, i) {
  val.cummulative = cummulative;
  cummulative += val.values.length;
  val.values.forEach(function(values) {
    values.parentKey = val.key;
    rangeBands.push(i);
  })
});
//console.log(data);

var x_category = d3.scale.linear()
  .range([0, width]);


var x_defect = d3.scale.ordinal().domain(rangeBands).rangeRoundBands([0, width], .1);
var x_category_domain = x_defect.rangeBand() * rangeBands.length;
x_category.domain([0, x_category_domain]);


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

y.domain([0, d3.max(data, function(cat) {
  return d3.max(cat.values, function(def) {
    return def.value;
  });
})]);

var category_axis = d3.svg.axis()
  .scale(x_category)
  .orient("bottom");

var yAxis = d3.svg.axis()
  .scale(y)
  .orient("left")
  .tickFormat(d3.format(".2s"));

var svg = d3.select("body").append("svg")
  .attr("width", width + margin.left + margin.right)
  .attr("height", height + margin.top + margin.bottom)
  .style('background-color', 'EFEFEF')
  .append("g")
  .attr("transform", "translate(" + margin.left + "," + margin.top + ")");

svg.append("g")
  .attr("class", "y axis")
  .call(yAxis)
  .append("text")
  .attr("transform", "rotate(-90)")
  .attr("y", 6)
  .attr("dy", ".71em")
  .style("text-anchor", "end")
  .text("Value");

var category_g = svg.selectAll(".category")
  .data(data)
  .enter().append("g")
  .attr("class", function(d) {
    return 'category category-' + d.key;
  })
  .attr("transform", function(d) {
    return "translate(" + x_category((d.cummulative * x_defect.rangeBand())) + ",0)";
  })
  .attr("fill", function(d) {
    return color[d.key];
  });

var category_label = category_g.selectAll(".category-label")
  .data(function(d) {
    return [d];
  })
  .enter().append("text")
  .attr("class", function(d) {
    //console.log(d)
    return 'category-label category-label-' + d.key;
  })
  .attr("transform", function(d) {
    var x_label = x_category((d.values.length * x_defect.rangeBand() + barPadding) / 2);
    var y_label = height + 30;
    return "translate(" + x_label + "," + y_label + ")";
  })
  .text(function(d) {
    return d.key;
  })
  .attr('text-anchor', 'middle');

var defect_g = category_g.selectAll(".defect")
  .data(function(d) {
    return d.values;
  })
  .enter().append("g")
  .attr("class", function(d) {
    return 'defect defect-' + d.key;
  })
  .attr("transform", function(d, i) {
    return "translate(" + x_category((i * x_defect.rangeBand())) + ",0)";
  });

var defect_label = defect_g.selectAll(".defect-label")
  .data(function(d) {
    return [d];
  })
  .enter().append("text")
  .attr("class", function(d) {
    //console.log(d)
    return 'defect-label defect-label-' + d.key;
  })
  .attr("transform", function(d) {
    var x_label = x_category((x_defect.rangeBand() + barPadding) / 2);
    var y_label = height + 10;
    return "translate(" + x_label + "," + y_label + ")";
  })
  .text(function(d) {
    return d.key;
  })
  .attr('text-anchor', 'middle');


var rects = defect_g.selectAll('.rect')
  .data(function(d) {
    return [d];
  })
  .enter().append("rect")
  .attr("class", "rect")
  .attr("width", x_category(x_defect.rangeBand() - barPadding))
  .attr("x", function(d) {
    return x_category(barPadding);
  })
  .attr("y", function(d) {
    return y(d.value);
  })
  .attr("height", function(d) {
    return height - y(d.value);
  });

category_g
  .append("line")
  .style("stroke", "black")
  .style("stroke-width", "4px")
  .style("stroke-linecap","round")
  .attr("x1", function(d) {
    var bbox = this.parentNode.getBBox();
    return bbox.width+7;
  })
  .attr("y1", height)
  .attr("x2", function(d) {
    var bbox = this.parentNode.getBBox();
    return bbox.width;
  })
  .attr("y2", height + 50);

/* Styles go here */

body {
  font: 10px sans-serif;
}
.axis path,
.axis line {
  fill: none;
  stroke: #000;
  shape-rendering: crispEdges;
}
.bar {
  fill: steelblue;
}
.x.axis path {
  display: none;
}

<!DOCTYPE html>
<html>

<head>
  <script data-require="d3@3.5.3" data-semver="3.5.3" src="//cdnjs.cloudflare.com/ajax/libs/d3/3.5.3/d3.js"></script>
  <link rel="stylesheet" href="style.css" />

</head>

<body>
  <h1>Hello Plunker!</h1>

</body>

</html>