SOURCE

console 命令行工具 X clear

                    
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console
<!-- <div class="radius-test1"></div>
 -->
<div class="semi-circle"></div>
.radius-test1 {
	width: 300px; 
	height: 200px; 
	background-color: #f00;
	border: 50px solid #cd0000; 
  border-radius: 300px/200px;
}
.semi-circle
{
    width:100px;
    height:50px;//高度是宽度的一半
    background-color:#f00;
    border-radius:50px 50px 0 0;//左上和右上至少为height值
}