code: function drawSteps(){
              let steps = svg.select('.chart-group').selectAll('.step').data(data);
  
              // Enter
              steps.enter()
                .append('rect')
                  .classed('step', true)
                  .attr('x', chartWidth) // Initially drawing the steps at the end of Y axis
                  .attr('y', ({value}) => yScale(value))
                  .attr('width', xScale.bandwidth())
                  .attr('height', (d) => (chartHeight - yScale(d.value)))
                  .on('mouseover', function(d) {
                      handleMouseOver(this, d, chartWidth, chartHeight);
                  })
                  .on('mousemove', function(d) {
                      handleMouseMove(this, d, chartWidth, chartHeight);
                  })
                  .on('mouseout', function(d) {
                      handleMouseOut(this, d, chartWidth, chartHeight);
                  })
                .merge(steps)
                  .transition()
                  .ease(ease)
                  .attr('x', ({key}) => xScale(key))
                  .attr('y', function(d) {
                      return yScale(d.value);
                  })
                  .attr('width', xScale.bandwidth())
                  .attr('height', function(d) {
                      return chartHeight - yScale(d.value);
                  });
  
              // Exit
              steps.exit()
                  .transition()
                  .style('opacity', 0)
                  .remove();
          }
docs: Draws the step elements within the chart group
  @private