body {
    font-family: sans-serif;
    margin: 0;
    padding: 0;
}

header {
    background-color: #333;
    color: #fff;
    padding: 20px;
    text-align: center;
}

h1 {
    margin-bottom: 10px;
}

nav {
    display: flex;
    justify-content: center;
}

nav ul {
    list-style: none;
    padding: 0;
}

nav li {
    display: inline-block;
    margin: 0 10px;
}

nav a {
    color: #fff;
    text-decoration: none;
    padding: 10px;
}

nav a:hover {
    background-color: #ddd;
    color: #333;
}

.submenu {
    display: none;
    position: absolute;
    background-color: #ddd;
    padding: 10px;
    border-radius: 5px;
}

li:hover .submenu {
    display: block;
}

.submenu li a {
    display: block;
    padding: 5px 10px;
}

.submenu li a:hover {
    background-color: #eee;
}

footer {
    background-color: #333;
    color: #fff;
    padding: 10px;
    text-align: center;
    margin-top: 20px;
}