Colors and proportions from Wikipedia.
height: 160px;
width: 220px;
background-image:
linear-gradient(top, #002868, #002868),
linear-gradient(top, #002868, #002868),
linear-gradient(top, #fff, #fff),
linear-gradient(top, #fff, #fff);
background-position: 0 50%, 35% 0, 0 50%, 33.5% 0;
background-color: #EF2B2D;
background-size: 100% 13%, 9.5% 100%, 100% 25%, 18.5% 100%;
background-repeat: no-repeat;
height: 160px;
width: 220px;
background-image:
linear-gradient(top, #00296c, #002765),
linear-gradient(top, #003282, #001e4f),
linear-gradient(top, #fafafa, #f4f4f4),
linear-gradient(top, #fff, #eee),
linear-gradient(top, #fa2d30, #bf2225);
background-position: 0 50%, 35% 0, 0 50%, 33.5% 0, 0 0;
background-size: 100% 13%, 9.5% 100%, 100% 25%, 18.5% 100%, 100% 100%;
background-repeat: no-repeat;
box-shadow: 0 1px 5px rgba(0,0,0,0.25), 0 0 1px #fff inset;