html, body {
    margin: 0;
    height: 100%;
    font-family: "Lucida Sans", sans-serif;
}

* {
    box-sizing: border-box;
}

h1, h2 {
    margin-top: 10px;
}

form {
    margin: 0;
}

header {
    background-color: #016f1d;
    text-align: center;
    color: #fff;
}