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

:root {
  --flag-height: 2;
  --flag-width: 3;
  --czech-white: #ffffff;
  --czech-red: #d7141a;
  --czech-blue: #11457e;
}

#czech-republic {
  position: relative;
  height: 180px;
  aspect-ratio: var(--flag-width) / var(--flag-height);
  background: linear-gradient(
    180deg,
    var(--czech-white) 0%,
    var(--czech-white) 50%,
    var(--czech-red) 50%,
    var(--czech-red) 100%
  );
}

#czech-republic::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0;
  width: 50%;
  height: 100%;
  background: var(--czech-blue);
  clip-path: polygon(0 0, 100% 50%, 0 100%);
}