.button-back-to-top {
    position: fixed;
    bottom: 30px;
    right: 30px;
    width: 50px;
    height: 50px;
    background-color: #0073ad;
    color: white;
    border: none;
    border-radius: 25px;
    text-align: center;
    font-size: 24px;
    width: 50px;
    box-shadow: 0 2px 5px rgba(0, 0, 0, 0.3);
    opacity: 0;
    visibility: hidden;
    transition: opacity 0.3s, visibility 0.3s;
}

.button-back-to-top.visible {
    opacity: 1;
    visibility: visible;
}

.button-back-to-top:hover {
    background-color: #47a6d5, !important;
}

.button-back-to-top:focus {
    outline: none, !important;
}