div.polaroid {
    width: 250px;
    background-color: white;
    height: auto;
    box-shadow: 0 4px 8px 0 rgba(0, 0, 0, 0.2), 0 6px 20px 0 rgba(0, 0, 0, 0.19);
    margin-bottom: 25px;
 }
 div.container {
    text-align: center;
    padding: 10px 20px;
 }
 .flex-container {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
 }
    .flex-container > div {
    text-align: center;
 }
 .thumbnail {
    background-color: black;
    width: 240px;
    height: 200px;
    display: inline-block; /* makes it fit in like an <img> */
    background-size: cover; /* or contain */
    background-position: center center;
    background-repeat: no-repeat;
    padding-top: 10px;
 }