div#element_to_pop_up{
    background-color: #fff;
    border-radius: 10px 10px 10px 10px;
    box-shadow: 0 0 25px 5px #999;
    color: #20b8f9;
    display: none;
    min-width: 300px;
    padding: 25px;
    text-align: center;
    font-weight: bold;
}
div#element_to_pop_up.maxvaluereached{
  background-color: #ff0000;
  color:#fff;
}
div#element_to_pop_up.emptycart{
  background-color: #000;
  color:#fff;
}