.topvideobild {
    position: relative;
    padding-bottom: 56.25%;
    background-size: cover;
    background-repeat: no-repeat;
    background-position: center;
}
.topvideobild iframe {
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    z-index: 0;
    height: 100%;
    width: 100%;
    border: 0;
}

.topvideobild .overlay {
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    width: calc(100% - 30px);
    height: calc(100% - 30px);
    z-index: 1;
    margin: auto;
    background-color: rgba(255, 255, 255, 0.75);
    color: #000;
    padding: 10px;
    display: flex;
    justify-content: center;
    align-items: center;
    text-align: center;
}

.topvideobild .inner_overlay {
    width: 600px;
    max-width: 100%;
}