body {
    font-family: Ubuntu, sans-serif;
    margin: 0;
    padding: 0;
    background-color: whitesmoke;
    color: #222222;
}

header, footer {
    background-color: #222222;
    color: whitesmoke;
    padding: 1rem 2rem;
}

.header-inner {
    max-width: 680px;
    margin: 0 auto;
    padding: 1rem 2rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

header a, footer a {
    color: whitesmoke;
    text-decoration: none;
}

header a:hover, footer a:hover {
    text-decoration: underline;
}

nav ul {
    list-style: none;
    display: flex;
    gap: 1.5rem;
    padding: 0;
    margin: 0;
}

.nav-group {
    display: flex;
    align-items: center;
    gap: 1rem;
}

main {
    max-width: 680px;
    margin: 2rem auto;
    padding: 0 1rem;
}

section {
    background-color: #ffffff;
    padding: 1.5rem;
    margin-bottom: 1.5rem;
}

img {
    max-width: 100%;
}

#hamburger {
    display: none;
}

@media (max-width: 680px) {
    main {
        margin: 1rem 0;
    }
    #hamburger {
        display: block;
    }
    nav ul {
        display: none;
    }
    nav ul.show {
        display: flex;
        flex-direction: column;
    }
}

.footer-row {
    display: flex;
    max-width: 680px;
    justify-content: space-between;
    align-items: center;
    margin: 0 auto;
}