CSS⼊⻔
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>Document</title>
<style>
div {
width: 100px;
height: 100px;
background-color: red;
background-color: blue;
}
</style>
</head>
<body>
<div></div>
</body>
</html>
