.masonry {
    margin: 1.5em 0;
    padding: 0;
    column-gap: 1.5em;
    -moz-column-gap: 1.5em;
    -webkit-column-gap: 1.5em;
}

.item {
    display: inline-block;
    background: #fff;
    margin: 0 0 1.5em;
    width: 100%;
    box-sizing: border-box;
    -moz-box-sizing: border-box;
    -webkit-box-sizing: border-box;
}

@media only screen and (min-width: 1100px) {
    .masonry {
        -moz-column-count: 1;
        -webkit-column-count: 1;
        column-count: 1;
    }
}

@media only screen and (min-width: 1367px) {
    .masonry {
        -moz-column-count: 2;
        -webkit-column-count: 2;
        column-count: 2;
    }
}

@media only screen and (min-width: 1920px) {
    .masonry {
        -moz-column-count: 3;
        -webkit-column-count: 3;
        column-count: 3;
    }
}