@media (min-width: 576px) {
  .dropdown:hover > .dropdown-menu {
    display: block;
    margin-top: 0;
  }

  .dropdown-menu > .dropdown:hover > .dropdown-menu {
    display: block;
    margin-top: -9px;
  }

  .dropdown-menu > .dropdown > .dropdown-menu {
    left: 100%;
    top: 0;
  }

}

.dropdown-menu {
  transition: all 0.3s ease;
}

.navbar-nav .dropdown-menu {
  border-radius: unset;
}

.dropdown-menu li.dropdown > .dropdown-item::after {
  display: inline-block;
  margin-left: 0.255em;
  vertical-align: 0.255em;
  content: "";
  border-top: 0.3em solid;
  border-right: 0.3em solid transparent;
  border-bottom: 0;
  border-left: 0.3em solid transparent;
}

.dropdown-menu li.dropdown:hover > .dropdown-item::after {
  transition: .3s;
  transform: rotate(-90deg);
}