do not directly apply scales to data, compose them with accessor functions instead

scales.js

// accessor functions to decouple from data shape
const x = d => d.date
const y = d => d.score
 
 const xScale = d3.scaleTime()
   .range([0, width])
   .domain(xExtent)
 
const yScale = d3.scaleLinear()
  .range([height, 0])
  .domain(yDomainPadded)

// compose scaling with accessors of path generator
const line =d3.line()
  .x(d => xScale(x(d)))
  .y(d => yScale(y(d)))

/* do not scale data directly 
const data = rawData.map(datum=>({...datum, x: xScale(datum.date),y: yScale(datum.score)}))* /