#backToTop {
    display: none;

    position: fixed;
    bottom: 25px;
    right: 25px;
    z-index: 99999;

    width: 50px;
    height: 50px;

    background: #337ab7;
    color: #fff;

    border: none;
    border-radius: 50%;

    font-size: 20px;
    cursor: pointer;
}

.indexing-services img {
    filter: grayscale(100%);
    opacity: 0.60;
    transition: filter 0.35s ease, opacity 0.35s ease, transform 0.35s ease;
}

.indexing-services a:hover img {
    filter: grayscale(0%);
    opacity: 1;
    transform: scale(1.06);
}