<!DOCTYPE html>
<html>
<head>
<title>a</title>
<meta name="content-type" content="text/html; charset=UTF-8">
<style>
span {
display: block;
30px;
margin: 20px;
border-radius: 8px;
padding: 20px 50px;
text-align: center;
background: green;
}
span:active::after {
30px;
background: pink;
}
span::after {
content: '';
20px;
height: 20px;
display: block;
background: red;
transition: all .2s ease-in-out;
}
</style>
</head>
<body>
<span></span>
</body>
</html>