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

nav ul li {
    display: inline;
    margin-right: 20px;
}

header {
    background-color: #e0e0e0;
    color: #000000;
    text-align: center;
    padding: 10px 0;
}

nav a {
    text-decoration: none;
    color: #343434;
    font-weight: bold;
}