header nav {
    padding-top: 0;
    background-color: #eaeaea;
    padding: 1em;
}

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

header nav ul li {
    margin: 0 15px;
}

header nav ul li a {
    text-decoration: none;
    color: black;
    padding: 10px 15px;
    transition: background-color 0.2s;
}

header nav ul li a:hover {
    background-color: #d4d4d4;
    border-radius: 4px;
}

header nav ul li a.active {
    padding-bottom: 8px;
    border-bottom: 2px solid #007bff;
    background-color: #d0d0d0;
    border-radius: 4px;
}