.red_tmp_back_to_top_container {
    position: fixed;
    width: auto;
    bottom: 20px;
    cursor: pointer;
    text-align: center;
    opacity: 0;
    visibility: hidden;
    transition: all 0.3s;
    z-index: 9999;
    pointer-events: none; /* impedisce il click quando è nascosto */
}
.red_tmp_back_to_top_container.visible {
    opacity: 1;
    visibility: visible;
    pointer-events: auto;
}
.red_tmp_back_to_top_container.bottom_right{
    right: 20px;
}
.red_tmp_back_to_top_container.bottom_left{
    left: 20px;
}
.icon_back_to_top,
.icon_back_to_top i:before{
    transition: all 0.3s;
}