body {
    background-color: whitesmoke;
    font-family: 'Trebuchet MS', 'Lucida Sans Unicode', 'Lucida Grande', 'Lucida Sans', Arial, sans-serif;
    font-size: medium;
}

a {
    color: unset;
    text-decoration: none;
}

header {
    width: 100%;
    text-align: center;
}

header > nav {
    width: 100%;
    display: flex;
    justify-content: space-evenly;
    align-items: center;
    margin-top: 0.8em;
}

header > nav > li {
    width: 20%;
    min-width: fit-content;
    border: 1px black solid;
    padding: 0.25em;
    border-radius: 0.25em;
    transition: 500ms;
    white-space: nowrap;
    list-style: none;
}

header > nav > li:hover{
    cursor: pointer;
    background-color: rgb(0, 0, 0);
    box-shadow: 0px 0px 1em black;
    transition: 500ms;
    color: whitesmoke;
}

header > nav > li > a {
    display: block;
    width: 100%;
    height: 100%;
}

div[id=body] {
    padding: 1em;
    text-align: justify;
}

footer {
    border-top: 1px black solid;
    padding-top: 1em;
}

p[id=copyright] {
    text-align: center;
}

nav[id=nav-footer] {
    text-align: center;
    list-style: none;
}

nav[id=nav-footer] > li {
    width: 100%;
}

nav[id=nav-footer] > li:hover {
    color: blue;
    cursor: pointer;
}