.menu ul {
    background-color: orange;
    display: flex;
}
.menu a {
    display: block;
    padding: 25px;
    text-decoration: none;
    color: white;
}
.menu li {
    position: relative;
}
.menu li ul{
    display: none;
    position: absolute;
    flex-direction: column;
}
.menu li li {
    width: 10rem;
}
.menu li li:nth-child(even) {
    background-color: rgba(0, 0, 0, 0.1);
}
.menu a:hover {
    background-color: rgba(255, 255, 255, 0.25);
}
.menu li:hover > ul {
    display: block;
}
.menu li ul ul {
    left: 10rem;
    top: 0;
}
.menu li a:first-child:nth-last-child(2):before {
    content: "";
    display: block;
    position: absolute;
    height: 10px;
    width: 10px;
    clip-path: polygon(87% 50%, 0 0, 0 100%);
    background-color: white;
    top: 50%;
    transform: translateY(-50%);
    right: 10px;
}