.div_scroll{
    right: 10px; 
    bottom: 35px; 
    display: none; 
    z-index: 1
}
.btn_scroll{
     background-color: #0f351cff;
      width: 40px;
      height: 40px;
      border-radius: 50px;
}

.img_btn_scroll{
    width: 15px
}