cz.svg 231 Bytes
<svg xmlns="http://www.w3.org/2000/svg" id="flag-icon-css-cz" viewBox="0 0 640 480">
  <path fill="#ffffff" d="M0 0h640v240H0z"/>
  <path fill="#d7141a" d="M0 240h640v240H0z"/>
  <path fill="#11457e" d="M360 240 0 0V480z"/>
</svg>