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  Hey, you made it all the way down to the last demo in this
  nerdy blog post about ch units. That’s awesome! There’s not
  much more to read after this, so if you’re feeling antsy,
  know that you’re almost done. I’m pretty much ready to get
  out of here, too, you know. Maybe we can go get Dairy Queen
  or something after.

.chUnits width: 65ch * 0.7257


  font-family: 'Georgia', serif
  font-size: 20px
  line-height: 1.5
  padding: 40px

  margin: 0 auto 1em
  width: 65ch * 0.7257

  background-color: rgba(red, 0.1)
  display: block
  height: 30px
  margin: 0 auto
  width: 65ch * 0.7257
  text-indent: 20px