style.css

* {
    margin: 0px;
    padding: 0px;
    box-sizing: border-box;
    font-size: inherit;
}

html {
    font-size: 1.2rem;
}

@media (max-width: 60rem) {
    body {
        width: 96vw;
        height: 100vh;
        
        margin: 0 auto;
        padding: 1rem;
    
        display: grid;
        grid-template-rows: min-content 1fr;
        row-gap: 1rem;
    }
}

@media (min-width: 60rem) {
    body {
        width: 100%;
        height: 100vh;

        padding: 1rem;
    
        display: grid;
        grid-template-columns: 24rem 1fr;
        column-gap: 1rem;
    }
}

div#controls {
    font-family: serif;
    height: min-content;

    display: flex;
    flex-direction: column;
}

div#controls > input[type=text], div#controls > select, div#controls > button {
    background-color: white;
    border: 1px solid black;
    border-radius: 2px;
    padding: 2px;
}

div#controls > select {
    box-shadow: -1px -1px rgb(210, 210, 210) inset;
}

div#controls > button {
    margin-top: 2px;
    box-shadow: -2px -2px rgb(210, 210, 210) inset;
}

div#controls > :focus {
    outline: #ff920d solid 1px;
}

div#display {
    width: 100%;
    max-height: 100%;
}

div#display > canvas {
    max-width: 100%;
    max-height: 100%;
}