.srgallery-flex-grid {
    width: 100%;
}

.demo-photobox {
    position: absolute;
}

.demo-photobox img {
    height: 100%;
    width: 100%;
    object-fit: cover;
}

.srgallery-caption {
    position: absolute;
    bottom: 0;
    background: rgba(0,0,0,0.3);
    color: white;
    width: 95%;
    text-align: center;
    padding: 5px;
    font-size: 1.5em;
}