.dropdown-custom {
    position: relative;
}

.dropdown-menu-custom {
    position: absolute;
    top: calc(100% + .25rem);
    left: 0;
    display: none;
    min-width: 12rem;
    padding: .5rem 0;
    background:rgba(0,0,0,.2);
    border-radius: .5rem;
    box-shadow: 0 6px 16px rgba(0, 0, 0, .15);
    z-index: 1050;
}

.dropdown-item-custom {
    padding: .5rem 1rem;
    display: block;
    color: var(--background-color);
}

.dropdown-item-custom:hover {
    background: rgba(255, 255, 255, .4);
    color: var(--primary-color);
}

.dropdown-custom.show .dropdown-menu-custom {
    display: block;
}

.dropdown-custom-icon {
  transition: transform .3s ease;   /* smooth quarter-second spin */
}

.dropdown-custom.show .dropdown-custom-icon { transform: rotate(180deg) !important; }