/* reference: https://en.wikipedia.org/wiki/Flag_of_Taiwan */

:root {
  --flag-height: 2;
  --flag-width: 3;
  --taiwan-red: #FE0000;
  --taiwan-blue: #000095;
}

#taiwan {
  position: relative;
  height: 180px;
  aspect-ratio: var(--flag-width) / var(--flag-height);
  background: var(--taiwan-red);
}

#taiwan::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  width: 40%;
  height: 50%;
  background: var(--taiwan-blue);
}