.navbar {
    float:none;
    margin:0 auto;
    display: block;
    text-align: center;
}

.navbar-nav > li {
    display: inline-block;
    float:none;
}

.card-img-top {
    width: 100%;
    height: 7vw;
    object-fit: cover;
}

.abstand {
	margin-left: 5px;
}