Codice
<style>
.container {
display: flex;
height: 200px;
background-color: #f0f0f0;
align-items: stretch; /* default */
}
.item {
width: 100px;
height: 50px;
background-color: orange;
}
.center {
align-self: center; /* centra verticalmente */
}
</style>
</head>
<body>
<div class="container">
<div class="item center">Center</div>
</div>