.fss {
    --fss-item-size: 50px;
    --fss-content-width: 12ch;
    --fss-transition: 300ms;
    --fss-color: white;
    --fss-item-bg: var(--bs-primary);
    --fss-space-to-screen-border: 20px;

    color: var(--fss-color);

    position: fixed;
    bottom: var(--fss-space-to-screen-border);
    left: 0;
    right: 0;

    display: flex;
    flex-direction: row;
    justify-content: center;
    gap: .5rem;
}

@media screen and (min-width: 576px) {
    .fss {
        flex-direction: column;
        align-items: flex-end;
        bottom: 0;
        left: unset;
        top: 0;
        right: var(--fss-space-to-screen-border);

    }
    
}


.fss-item {

    color: var(--fss-color);

    display: flex;
    align-items: center;

    height: var(--fss-item-size);
    width: var(--fss-item-size);
    border-radius: var(--fss-item-size);
    border: 1px solid;
    border-color: var(--fss-item-bg);
    background: var(--fss-item-bg);

    box-shadow: 2px 3px 4px rgba(0, 0, 0, 0.25);

    overflow: hidden;
    transition: var(--fss-transition);
}


.fss-item:hover {
    text-decoration: none;
    filter: brightness(120%);
}

@media screen and (min-width: 576px) {
    .fss-item:has(.fss-content):hover {
        width: calc(var(--fss-item-size) + var(--fss-content-width));
        
    } 
}


@media screen and (min-width: 576px) {
    .fss-item:hover .fss-content {
        width: var(--fss-content-width);
        opacity: 1;
    }
}


.fss-icon {
    display: block;
    text-align: center;
    width: var(--fss-item-size);
    font-size: 1.2rem;
}

.fss-content {
    width: 0;
    opacity: 0;
    transition: var(--fss-transition);
}

.fss-content::before {
    content: "";
    height: 100%;
    border: 1px solid var(--fss-color);
    opacity: .25;
    margin-right: 1rem;
}

#fss-up {
    position: absolute;
    bottom: 0;
    right: var(--fss-space-to-screen-border)
}

@media screen and (min-width: 576px) {
    #fss-up {
        bottom: var(--fss-space-to-screen-border);
        right: 0;
    }
    
}


@media screen and (max-width: 399px) {
    .fss-item:has(.fss-content) {
        display: none;
    }
    
}