.modal-overlay{
    display: none;
    position: fixed;
    background: rgba(0, 0, 0, .2);
    top: 0;
    left: 0;
    bottom: 0;
    right: 0;
    z-index: 2;
}
.modal{
    max-width: 550px;
    text-align: center;
    background: white;
    padding: 20px;
    box-sizing: border-box;
    border-radius: 15px;
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
}
.close{
    font-weight: bold;
    font-size: 30px;
    cursor: pointer;
    position: absolute; 
    top: 0;
    right: 10px;

}

/* стрелка вверх */
#up{
    display: none;
    position: fixed;
    bottom: 50px;
    right: 50px;
    background: pink;
    padding: 20px;
    border-radius: 50%;
}
#up>i{
    color: white;
}