彩虹.html
<!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>
<style>
.box {
width: 600px;
height: 300px;
border: 1px solid red;
overflow: hidden;
}
.layer {
width: 600px;
height: 600px;
border: 1px solid blue;
background-image: radial-gradient(
50% 50%,
#fff 20%,
pink 30%,
pink 35%,
red 40%,
red 45%,
green 50%,
green 55%,
yellow 60%,
yellow 65%,
blue 70%,
blue 75%,
orange 80%,
orange 85%,
#fff 90%
);
}
</style>
</head>
<body>
<div class="box">
<div class="layer"></div>
</div>
</body>
</html>