nav {
    background-color: var(--primary-color);
    padding: 15px 0;
    width: 100%;
    display: flex;
    justify-content: center;
    margin-bottom: 20px;
}

nav a {
    color: white;
    padding: 10px 15px;
    margin: 0 5px;
    border-radius: 5px;
    transition: background-color 0.3s ease;
}

nav a:hover {
    background-color: rgba(255, 255, 255, 0.1);
}

@media (max-width: 640px) {
    nav {
        flex-wrap: wrap;
    }

    nav a {
        flex: 1 1 40%;
        text-align: center;
        margin: 5px;
    }
}