co.svg 289 Bytes
<svg xmlns="http://www.w3.org/2000/svg" id="flag-icon-css-co" viewBox="0 0 640 480">
  <g fill-rule="evenodd" stroke-width="1pt">
    <path fill="#ffe800" d="M0 0h640v480H0z"/>
    <path fill="#00148e" d="M0 240h640v240H0z"/>
    <path fill="#da0010" d="M0 360h640v120H0z"/>
  </g>
</svg>