align div verticaly and horizontaly in th page in CSS flex code example
Example: css center image horizontal and vertical flexbox
<!doctype html>
<html lang="en">
<head>
<meta charset="utf-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>Center Flex Item Image</title>
<style>
.box {
width:80%;
min-height:80vh;
margin:auto;
border:1px solid;
display: flex;
align-items: center;
justify-content: center;
}
.box img {
display: block;
width: 80%;
min-width:100px;
max-width: 350px;
height: auto;
margin: auto;
}
</style>
</head>
<body>
<div class="box">
<img src="http://via.placeholder.com/350x250" width="350" height="250" alt="missing image">
</div>
</body>
</html>