.dropdown-item {
  color: #fff;
}
.dropdown .dropdown-menu {
  display: none;
  background: #000;
}
.dropdown:hover>.dropdown-menu, 
.dropend:hover>.dropdown-menu {
  display: block;
  margin-top: .1em;
  margin-left: .1em;
}
@media screen and (min-width:769px) {
  .dropend:hover>.dropdown-menu {
    position: absolute;
    top: .1em;
    left: 100%;
  }
  .dropend .dropdown-toggle {
    margin-left: .5em;
  }
}