.row {
    display: flex;
    flex-wrap: wrap;
    padding: 0 4px;
}

/* Create four equal columns that sits next to each other */
.column {
    flex: 25%;
    max-width: 25%;
    padding: 0 4px;
}

.column img {
    margin-top: 8px;
    vertical-align: middle;
    width: 100%;
    transition: transform 0.3s;
    border-radius: 8px;
}

.column img:hover {
    transform: scale(1.02);
}

/* Responsive layout - makes a two column-layout instead of four columns */
@media screen and (max-width: 800px) {
    .column {
        flex: 50%;
        max-width: 50%;
    }
}

/* Responsive layout - makes the two columns stack on top of each other instead of next to each other */
@media screen and (max-width: 600px) {
    .column {
        flex: 100%;
        max-width: 100%;
    }
}

.modal {
    display: none;
    position: fixed;
    z-index: 2000;
    padding-top: 60px;
    left: 0; top: 0;
    width: 100%; height: 100%;
    overflow: auto;
    background-color: rgba(0,0,0,0.9);
}
.modal-content {
    margin: auto;
    display: flex;
    justify-content: center;
    align-items: center;
    max-width: 90vw;
    max-height: 80vh;
}
.modal-content img {
    width: auto;
    height: auto;
    max-width: 100%;
    max-height: 80vh;
    display: block;
    object-fit: contain;
}
.modal-content source { max-width: 100%; max-height: 100%; }
.close {
    position: absolute;
    top: 30px; right: 50px;
    color: #fff;
    font-size: 40px;
    cursor: pointer;
}
.prev, .next {
    cursor: pointer;
    position: absolute;
    top: 50%;
    width: auto;
    margin-top: -22px;
    padding: 16px;
    color: #fff;
    font-weight: bold;
    font-size: 40px;
    user-select: none;
    transition: 0.3s;
}
.prev { left: 20px; }
.next { right: 20px; }
.prev:hover, .next:hover { color: #3498db; }
@media (max-width: 600px) {
    .modal-content { max-width: 95vw; max-height: 70vh; }
    .modal-content img { max-width: 100%; max-height: 70vh; }
    .close { right: 10px; }
    .prev, .next { font-size: 32px; }
}