#scrollToTopBtn {
    position: fixed;
    bottom: 60px;
    right: 40px;
    width: 50px;
    height: 50px;
    border-radius: 50%;
    background-color: #212529;
    color: #ffffff;
    border: none;
    cursor: pointer;
    box-shadow: 0 4px 10px rgba(0,0,0,0.2);
    z-index: 9998;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.2rem;
    opacity: 0;
    visibility: hidden;
    transition: opacity 0.3s ease, visibility 0.3s ease, background-color 0.2s ease;
}

#scrollToTopBtn.visible {
    opacity: 1;
    visibility: visible;
}

#scrollToTopBtn:hover {
    background-color: #495057;
}