.video-container {
    position: relative;
}

#changeVideo {
    position: absolute;
    top: 2.5rem;
    left: 2rem;
    width: 30px;
    height: 30px;
    opacity: 0;
    transition: opacity .3s ease;
    cursor: pointer;
    border-radius: 50%;
    background: #FFFFFFDD;
    font-weight: bold;
    line-height: 25px;
    text-align: center;
}

@media (max-width:767.98px) {
    #changeVideo {
        top: 4rem;
        left: 2rem;
    }
}
@media (max-width:534.98px) {
    #changeVideo {
        top: 7rem;
        left: 2rem;
    }
}

/* On hovering the video, show the button */
video:hover~#changeVideo {
    opacity: 1;
}

#changeVideo:hover {
    opacity: 1;
}