.dreispalter {
	position: relative;
}

.elem3 {
    -webkit-box-sizing: border-box;
    -moz-box-sizing: border-box;
    -ms-box-sizing: border-box;
    -o-box-sizing: border-box;
    box-sizing: border-box;
    float: left;
    margin-right: 5%;
    width: 29.33%;
}

.elem3:last-child {
    margin-right: 0;
}

@media (max-width: 991px) {
	.dreispalter .holder {
		display: flex;
		flex-direction: column;
		flex-flow: row wrap;
	}
	.elem3 {
	    width: 47.5%;
	}

	.elem3:nth-child(2n) {
	    margin-right: 0;
	}
}

@media (max-width: 650px) {
    .elem3 {
        width: 100%;
        margin-right: 0;
    }
}