.nav-demo {
    background: #2c3e50;
    border-radius: 8px;
    overflow: hidden;
}

.nav-demo ul {
    margin: 0;
    padding: 0;
    list-style: none;
    display: flex;
}

.nav-demo li {
    flex: 1;
}

.nav-demo a {
    display: block;
    padding: 15px;
    color: white;
    text-decoration: none;
    text-align: center;
    transition: background 0.3s ease;
}

.nav-demo a:hover {
    background: #34495e;
}

@media (orientation: portrait) {
    .nav-demo ul {
        flex-direction: column;
    }
    .nav-demo li {
        border-bottom: 1px solid #34495e;
    }
    .nav-demo li:last-child {
        border-bottom: none;
    }
}

@media (orientation: landscape) {
    .nav-demo ul {
        flex-direction: row;
    }
    .nav-demo li {
        border-right: 1px solid #34495e;
    }
    .nav-demo li:last-child {
        border-right: none;
    }
}