style.css

body {
    background: #444;
    color: #ddd;
    text-align: center;
    margin: 0;
    padding: 0;
    overflow-x: hidden;
}

img {
    max-width: 300px;
    margin-bottom: 10px;
}

canvas {
    border: 3px inset white;
    border-radius: 5px;
    background-image: repeating-linear-gradient(#111, #222 0.4%);
    margin-top: 5px;
}

section {
    width: 400px;
    margin: auto;
    padding: 3px;
    text-align: left;
    background-image: repeating-linear-gradient(#222, #111 0.5%);
    border: 3px inset white;
    border-radius: 5px;
    margin-top: 5px;
    color: lime;
    font-family: consolas;
    font-size: 18px;
}

button {
    min-width: 2em;
    background: #222;
    color: goldenrod;
    border: 2px outset goldenrod;
    font-size: large;
}

button:hover {
    cursor: pointer;
    color: #ffc125;
    border-color: #ffc125;
}

button:disabled {
    background: #111;
    color: #966b00;
    border-color: #966b00;
    cursor: default;
}

article {
    width: 400px;
    font-family: consolas;
    font-size: 18px;
    color: lime;
    margin: -5px;
    margin: auto;
}

#lamp {
    width: 25px;
    height: 25px;
    border: 3px inset white;
    border-radius: 50%;
    position: absolute;
    margin-top: -5px;
}

main {
    width: 100%;
    height: 100vh;
    position: absolute;
    background: #444;
    z-index: 99;
    font-family: consolas
}

#info {
    width: 60%;
    margin: auto;
    text-align: left;
    border: 3px inset white;
    border-radius: 5px;
    background-image: repeating-linear-gradient(#111, #222 0.4%);
    padding: 0px 7px;
    margin-bottom: 10px;
    color: lime;
    font-size: large;
}

.startBtn {
    font-size: x-large;
    margin-bottom: 10px;
}

ul {
    list-style-type: none;
    padding-left: 0px;
}

@media screen and (max-width:400px) {
    section {
        width: 300px;
    }
    article {
        width: 300px;
    }
    #info {
        width: 90%;
    }
}