@media screen and (min-width: 320px) {
    * {
        margin: 0;
        padding: 0;
    }

    body {
        display: flex;
        justify-content: center;
        flex-direction: column;
        gap: 20px;
        font-family: "Courier New", Courier, monospace;
        font-size: 15px;
        color: whitesmoke;
        background-color: #251b37;
        text-align: center;
        min-height: 100vh;
    }

    div.header ul {
        display: flex;
        gap: 15px;
        padding: 15px;
    }

    div.header ul li {
        list-style: none;
    }

    div.header ul li.first-item {
        margin-left: auto;
    }

    a {
        text-decoration: none;
        color: whitesmoke;
        font-size: 18px;
    }

    a:hover {
        text-decoration: underline yellow 3px;
    }

    div.main {
        padding-bottom: 50px;
        margin-top: auto;
    }

    button {
        margin: 10px 0;
        text-decoration: none;
        color: #f0de36;
        font-family: "Gill Sans", "Gill Sans MT", Calibri, "Trebuchet MS",
            sans-serif;
        font-weight: 700;
        font-size: 25px;
        border: 4px solid #f0de36;
        background-color: #251b37;
        padding: 8px 20px;
        box-shadow: inset 0 0 0 0 #f0de36;
        transition: box-shadow 0.5s;
    }

    button:hover {
        box-shadow: inset 250px 0 0 0 #f0de36;
        color: #251b37;
        cursor: pointer;
    }

    .footer {
        font-size: 10px;
        font-weight: 700;
        margin-top: auto;
        color: black;
        padding: 20px 90px;
        background-color: #f0de36;
        display: flex;
        justify-content: center;
        align-items: center;
    }
}

@media screen and (min-width: 768px) {
    div.footer {
        font-size: 15px;
    }
}