<style type="text/css"> *{margin: 0; padding: 0;} body { display: flex; align-items: center; justify-content: center; vertical-align: center; flex-wrap: wrap; align-content: center; } .row { display: flex; align-items:stretch; flex:auto; background-color: red; } .item { display: flex; height: 150px; flex:0 0 33%; align-items:center; justify-content:center; border: 1px solid #000; } @media screen and (max-width: 600px) { .row { flex-direction: column; } } </style> <div class="row"> <div class="item">1/3</div> <div class="item">1/3</div> <div class="item">1/3</div> </div>