html {
  /* Delete all but one of the following font-size declarations: */

  /* Use a 12px base font size. 16px x 75% = 12px */
  font-size: 75%;
  /* Use a 14px base font size. 16px x .875 = 14px */
  font-size: 87.5%;
  /* Use a 16px base font size. */
  font-size: 100%;

  /* Establish a vertical rhythm. */
  line-height: 1.5em;
}
