html {
    box-sizing: border-box;
    height: 100vh;
}

*, *::before, *::after {
    box-sizing: inherit;
}

body {
    margin: 0;
    padding: 0;
    height: 100vh;
    background-color: rgba(255, 215, 146, 0.52);
    border-style: solid;
    border-width: 4px;
    border-radius: 3px;
}

header {
    position: fixed;
    top: 3%;
    left: 3%;
    right: 3%;
    bottom: calc(100% - 200px);
    overflow-y: hidden;
}

    h1 {
        text-align: center;
        font-family: Helvetica, sans-serif;
        text-decoration: underline;
    }

    p#info {
        padding-top: 10px;
        padding-bottom: 10px;
        border-style: solid;
        border-width: 1px;
        border-color: black;
        border-radius: 5px;
        text-align: center;
        font-size: 20px;
        font-family: Helvetica, sans-serif;
        background-color: #3498db;
        color: white;
    }

main {
    position: fixed;
    top: 200px;
    left: 3%;
    right: 3%;
    bottom: 3%;
    overflow-y: scroll;
    display: block;
}

    main div {
        display: flex;
        flex-direction: row;
        justify-content: center;
        flex-wrap: wrap;
    }

        button {
            margin: 5px;
            padding: 0;
            width: 50px;
            height: 50px;
            font-size: 30px;
            border-radius: 5px;
            cursor: pointer
        }

        button:hover {
            transform: scale(1.1);
            background-color: white;
        }

p#message-box {
    position: fixed;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    padding: 20px;
    font-size: 40px;
    font-family: Helvetica, sans-serif;
    color: white;
    box-shadow: 10px 10px 10px black;
    border-radius: 5px;
    opacity: 0;
    display: flex;
    justify-content: center;
    align-items: center;
    text-align: center;
}

p.animate {
    animation-duration: 2000ms;
    animation-name: animate;
}

@keyframes animate {
    0% {
        opacity: 0;
        display: block;
    }
    25% {
        opacity: 1
    }
    75% {
        opacity: 1
    }
    100% {
        opacity: 0;
        display: none;
    }
}