话不多少，直接上代码。
效果如图：
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8" />
</head>
<body>
<div>
<style>
.box{
width: 200px;
height: 200px;
color: white;
overflow: hidden;
position: relative;
border: 1px solid black;
border-radius: 50%;
background-color: gray;
}
.box > div{
width: 100%;
height: 100%;
position: absolute;
left: 50%;
right: 50%;
transform-origin: 0% 0%;
}
#left {
transform: rotate(120deg);
background: orange;
}
#right {
transform: rotate(-30deg);
background: blue;
}
#bottom {
background: red;
top: 75%;
left: 6%;
}
</style>
<div class="box">
<div id="left">
</div>
<div id="right">
</div>
<div id="bottom">
</div>
</div>
</div>
</body>
</html>
