.dropdown-item {
    padding: 10px 10px;
}

.dropdown-item:hover {
    background: lightgray;
}

.dropdown-menu-left {
    max-height: 400px;
    overflow: auto;
    width: 100%;
    cursor: pointer;
}

/* // Medium devices (tablets, 768px and up) */
@media (min-width: 768px) {
    .dropdown-menu-left {
        width: 250px;
    }
}