index.css

.logo {
    max-width: auto;
    max-height: 60px;
    margin-left: 20px;
}

.responsiveCal iframe {
    width: 800px;
    height: 600px;
}

@media (max-width: 550px) {
    .responsiveCal {
        position: relative;
        padding-bottom: 75%;
        height: 0;
        overflow: hidden;
    }
    .responsiveCal iframe {
        position: absolute;
        top:0;
        left: 0;
        width: 100%;
        height: 100%;
    }
    .card-content {
        padding: 0!important;
    }
}