.units {
  font: 1.2rem/2rem;
  font: 8vw/9vw;
  font: 10vh/12vh;
  font: 12vm/15vm;
  font: 12vmin/15vmin;
  font: 1.2ch/1.5ch;
}

.math {
  a: 1 + 1;
  b: 2px / 2;
  c: 2px ./ 2;
  d: (10px / 10px);
  e: ((16px ./ 2) / 2) / 2;
  f: ((16px ./ 2) / 2) ./ 2;
}