.upper {
    display: flex;
    justify-content: flex-end;
    align-items: center;
    margin-right: 20px;
}
.btn-up {
    display: flex;
    justify-content: center;
    align-items: center;
    position: fixed;
    float: right;
    bottom: 240px;
    border-radius: 50%;
    width: 60px;
    height: 60px;
    font-size: 40px;
    font-weight: 900;
    border: none;
    color: var(--bs-body-bg);
    background-color: var(--bs-body-color);
    padding-top: 4px;
    opacity: 0.5;
    transition: 0.5s;
    cursor: pointer;
    z-index: 2;
}
.btn-up:hover {
    opacity: 1;
}
.btn-up_hide {
    display: none;
}
@media screen and (max-width:992px) {
    .btn-up {
    left: 50%;
    transform: translateX(-50%);
    bottom: 70px;
    }
}