【纯 CSS】画 多国国旗

<style>.uk {	  width: 300px;  height: 200px;  border: 1px solid #000;  box-shadow: 2px 2px 3px 3px rgba(0, 0, 0, .25);  margin-bottom: 20px;  background-image:    linear-gradient(90deg, #cf142b, #cf142b),    linear-gradient(0deg, #cf142b, #cf142b),     linear-gradient(90deg, #FFFFFF, #FFFFFF),    linear-gradient(0deg, #FFFFFF, #FFFFFF),     linear-gradient(35deg, transparent 45%, #ffffff 45%, #ffffff 48%, #cf142b 48%, #cf142b 51%, #ffffff 51%, #ffffff 56%, transparent 56%, transparent 100%),     linear-gradient(-35deg, transparent 45%, #ffffff 45%, #ffffff 50%, #cf142b 50%, #cf142b 53%, #ffffff 53%, #ffffff 56%, transparent 56%, transparent 100%);  background-position: 0 50%, 50% 0,0 50%, 50% 0, 0 100%, 100% 0;  background-size: 100% 20%, 16% 100%, 100% 33%, 25% 100%, 100% 100%, 100% 100%;  background-repeat: no-repeat;  background-color: #00247d;}</style>
<div class="uk"></div>