.mobile-contact {
    position: fixed;
    right: 20px;
    bottom: 18%;
    z-index: 1;
    width: 50px;
    height: 50px;
}
.buttons-holder {
       position: fixed;
    right: 0;
    bottom: 0;
    z-index: 99;
}
.buttons-holder a img {
    width: 22px;
    filter: invert(1);
}
.buttons-holder a {
    width: 50px;
    height: 50px;
    background: #000;
    border-radius: 100%;
    display: flex;
    align-items: center;
    justify-content: center;
    margin-bottom: 10px;
}