/* Standard desktop-højde */
.header-img {
    width: 100%;
    height: 180px;
    object-fit: cover;
}

/* Tablet */
@media (max-width: 992px) {
    .header-img {
        height: 140px;
    }
}

/* Mobil */
@media (max-width: 576px) {
    .header-img {
        height: 100px;
    }
}
<style>
/* Mobilvenlig tabelvisning */
@media (max-width: 768px) {
    table.table {
        display: block;
        width: 100%;
    }
    table.table thead {
        display: none;
    }
    table.table tr {
        display: block;
        margin-bottom: 12px;
        border: 1px solid #ddd;
        padding: 10px;
        border-radius: 6px;
        background: #fff;
    }
    table.table td {
        display: flex;
        justify-content: space-between;
        padding: 6px 0;
        border: none !important;
    }
    table.table td::before {
        content: attr(data-label);
        font-weight: bold;
        margin-right: 10px;
        color: #333;
    }
    a.btn-sm {
        width: 100%;
        text-align: center;
    }
}
</style>