#back-to-top {
    position: fixed;
    right: 20px;
    bottom: 2px;
    width: 45px;
    height: 45px;
    border-radius: 50%;
    background-color: black;
    color: #fff;
    display: none;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    z-index: 999;
    font-size: 18px;
    transition: all 0.3s ease-in-out;
    border: none;
    line-height: 1;
    padding: 15px;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
}

#back-to-top.show {
    display: flex;
    animation: slideUp 0.3s ease-in-out;
}

#back-to-top:hover {
    background-color: #1565c0;
    box-shadow: 0 6px 12px rgba(0, 0, 0, 0.15);
    transform: translateY(-2px);
}

#back-to-top:active {
    transform: translateY(0);
}

#back-to-top i {
    color: #fff !important;
    font-size: 20px;
}

@keyframes slideUp {
    from {
        opacity: 0;
        transform: translateY(10px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}