mixsy/style.css

:root {
    --bg: #ed9f96;
    --alt: #dc4c6b;
    --inverse: #444;
    --text: #7be5b3;
}

* {
    box-sizing: border-box;
    color: var(--text);
    font-family: sans-serif;
}

html, body {
    background-color: var(--bg);
    margin: 0;
    padding: 0;
}

button {
    background-color: var(--text);
    border: 0;
    border-radius: 2.5vmin;
    color: var(--alt);
    cursor: pointer;
    display: block;
    font-size: 5vmin;
}

h1, p {
    margin: 0;
    text-align: center;
}

h1 {
    font-size: 10vmin;
}

h2 {
    font-size: 5vmin;
    margin: 0;
    text-align: center;
}

img {
    display: block;
    height: 22vmin;
}

textarea {
    background-color: var(--inverse);
    border: 0;
    color: var(--text);
    font-family: monospace;
    height: 17vmin;
    padding: 0.5em;
    width: 100%;
}

#container {
    background-color: var(--alt);
    border-radius: 5vmin;
    height: 100vmin;
    width: 100vmin;
}

.centre {
    margin: 0 auto;
}

.left {
    float: left;
}

.row {
    width: 100%;
    height: calc(82vmin / 3);
}

.square {
    width: 50vmin;
    height: 100%;
    padding: 0.5em;
}