<!DOCTYPE html>
<html>
<head>
<title>Title of the document</title>
<style>
body {
background: #c2c2c2;
font-size: 90%;
}
div {
background: #fff;
width: 200px;
margin: 20px;
}
.flex-center {
background: #83d483;
color: #fff;
border: 5px solid #fff;
display: flex;
flex-direction: column;
justify-content: center;
height: 200px;
resize: vertical;
overflow: auto;
}
.flex-center span {
margin: 0;
padding: 15px;
}
</style>
</head>
<body>
<div class="flex-center">
<span>Example of vertically centered multiple lines in a flexbox container.</span>
</div>
</body>