.fbs-button {
    position: fixed;
    z-index: 9999;
    width: var(--fbs-button-size, 60px);
    height: var(--fbs-button-size, 60px);
    border-radius: 999px;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    box-shadow: 0 10px 24px rgba(0,0,0,.18);
    transition: box-shadow .2s ease, opacity .2s ease;
    text-decoration: none;
    overflow: hidden;
    line-height: 0;
    font-size: 0;
    -webkit-tap-highlight-color: transparent;
}

.fbs-button:hover,
.fbs-button:focus {
    box-shadow: 0 12px 28px rgba(0,0,0,.24);
    text-decoration: none;
}

.fbs-button,
.fbs-button:hover,
.fbs-button:focus,
.fbs-button:active {
    transform: none !important;
}

.fbs-button svg,
.fbs-button__image {
    width: var(--fbs-icon-size, 24px);
    height: var(--fbs-icon-size, 24px);
    display: block;
}

.fbs-button__image {
    object-fit: contain;
}

@media (max-width: 782px) {
    .fbs-button {
        width: var(--fbs-button-size-mobile, 54px);
        height: var(--fbs-button-size-mobile, 54px);
    }

    .fbs-button svg,
    .fbs-button__image {
        width: var(--fbs-icon-size-mobile, 20px);
        height: var(--fbs-icon-size-mobile, 20px);
    }
}