header {
    background-color: #333;
    color: #fff;
    padding: 10px 0;
    text-align: center;
}

nav {
    background-color: #333;
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
}

nav ul {
    list-style-type: none;
    padding: 0;
    margin: 0;
    display: flex;
    justify-content: center;
}

nav ul li {
    position: relative;
}

nav ul li a {
    display: block;
    padding: 15px 20px;
    color: #fff;
    text-decoration: none;
    transition: background-color 0.3s;
}

nav ul li a:hover {
    background-color: #555;
}

nav ul li .dropdown-content {
    display: none;
    position: absolute;
    background-color: #f9f9f9;
    min-width: 160px;
    box-shadow: 0 8px 16px rgba(0, 0, 0, 0.2);
    z-index: 1;
}

nav ul li .dropdown-content li a {
    color: #333;
    padding: 12px 16px;
}

nav ul li .dropdown-content li a:hover {
    background-color: #ddd;
}

nav ul li:hover .dropdown-content {
    display: block;
}