* {
    margin: 0;
    padding: 0;
}

html, body {
    height: 100%;
    font-family: 'Arial', sans-serif;
    background-color: #222;
    color: white;
}

a {
    color: #1E90FF;
    text-decoration: none;
}

a:hover {
    text-decoration: underline;
}

header {
    background-color: #111;
    text-align: center;
    font-size: 24px;
    font-weight: bold;
    color: #8fc830;
    height: 40px;
}

header div {
    display: flex;
    align-items: center;
    justify-content: space-between;
}

header div img {
    height: 20px;
    margin: 10px;
    margin-left: 12.5px;
    vertical-align: middle;
}

header div ul {
    list-style: none;
    display: flex;
}

header div ul li {
    cursor: pointer;
    height: 40px;
    line-height: 40px;
    color: #888;
    font-size: 16px;
    vertical-align: middle;
    align-items: center;
    justify-content: center;
    display: flex;
    padding: 0 5px;
    user-select: none;
}

header div ul li:hover {
    color: white;
    background-color: #333;
    border-bottom-left-radius: 5px;
    border-bottom-right-radius: 5px;
}

footer {
    background-color: #111;
    padding: 20px 0;
    text-align: center;
    color: #888;
    height: 30px;
}

main {
    padding: 20px;
    height: calc(100vh - 160px);
}