header {
    width: 100%;
    height: 7vh;

    display: flex;
    justify-content: space-around;
    align-items: center;

    position: fixed;

    background-color: rgb(245, 245, 245);

    border-bottom: 1px solid rgb(200, 200, 200);
}

header > h1 {
    font-size: 2rem;
    font-weight: bold;
}

header nav > ul {
    width: 100%;
    height: 100%;

    list-style: none;

    display: flex;
}

header nav > ul li {
    margin: 0 20px;
}

header nav > ul a {
    padding: 1vh 1.5vw;
    border-radius: 5px;

    color: white;
    background-color: #363636;
}

header nav > ul a:hover {
    background-color: #686868;
}