d3 vertical bar graph

<!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; }
    #chart {
      shape-rendering: crispEdges;
      display: block;
    	margin: 0 auto;
			margin-top: 100px;
    }
  </style>
</head>
<body>
  <script>
    const data = [100, 200, 175, 200, 120];
    const w = 350;
    const h = 250;
    
    const x = d3.scaleLinear()
								.domain([0, data.length])
    						.range([0, w]);
    
    const y = d3.scaleLinear()
    						.domain([0, d3.max(data)])
    						.range([0, h]);
    
    const svg = d3.select('body')
    						.append('svg')
    						.attr('id', 'chart')
    						.attr('width', w)
    						.attr('height', h);
    
    svg.selectAll('.bar')
    	 .data(data).enter()
    	 .append('rect')
    	 .classed('.bar', true)
    	 .attr('x', (d, i) => x(i))
    	 .attr('y', d => h - y(d))
    	 .attr('width', x(1) - 2)
    	 .attr('height', d => y(d))
    	 .attr('fill', 'steelblue')
    	 .attr('stroke', 'black');
    
  </script>
</body>

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