<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<meta http-equiv="X-UA-Compatible" content="ie=edge">
<title>单行文字垂直居中</title>
<style>
div {
width: 200px;
height: 40px;
background-color: pink;
line-height: 40px;
}
</style>
</head>
<body>
<div>我要居中</div>
</body>
</html>