<style>* {box-sizing: border-box;}.row {display: flex;flex-wrap: wrap;}.column {padding-top:5px;padding-right:5px;padding-bottom: 5px;padding-left: 10px;width: 300px;height: 300px;border: 3px double black;margin: 5px;background-size: 300px 250px;display: inline-block;}.img {display: block;margin-left: auto;margin-right: auto;width: 50%;}.center {display: block;margin-left: auto;margin-right: auto;width: 50%;} @media screen and (max-width: 600px) {.row {flex-direction: column;} </style>