<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta http-equiv="X-UA-Compatible" content="IE=edge">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>Document</title>
</head>
<style>
#box{
background: linear-gradient(to right, red 0%,red 50%,white 51%,white 100%);
border: 1px solid #ccc;
width: 200px;
height: 200px;
}
#box1{
background: linear-gradient(45deg, red 0%,red 30%,transparent 30%,transparent 40%,blue 40%,blue 60%, white 61%,white 100%);
border: 1px solid #ccc;
width: 200px;
height: 200px;
}
#box2{
background-image:radial-gradient(at left top,red 30%,transparent 40%,blue 40%,transparent 50%, white 61%);
border: 1px solid #ccc;
width: 200px;
height: 200px;
}
</style>
<body>
<div id="box"></div>
<br>
<div id="box1"></div>
<br>
<div id="box2"></div>
</body>
</html>
效果
