:root {
    color-scheme: light dark;
    --light: #fff;
    --lesslight: #efefef;
    --dark: #404040;
    --moredark: #000;
    line-height: 1.5em; /* This causes wrapping h1's to collapse too small */
    font-family: system-ui,
        -apple-system, /* Firefox supports this but not yet `system-ui` */
        'Segoe UI',
        Roboto,
        Helvetica,
        Arial,
        sans-serif,
        'Apple Color Emoji',
        'Segoe UI Emoji';
    font-size: 16px;
}

* {
    box-sizing: border-box;
    color: var(--dark);
}

button, input {
    font-size: 1em; /* Override browser default font shrinking*/
}

input {
    border: 1px solid var(--dark);
    background-color: var(--lesslight);
    border-radius: .25em;
    padding: .5em;
}

pre {
    background-color: var(--lesslight);
    margin: 0.5em 0 0.5em 0;
    padding: 0.5em;
    overflow: auto;
}

code {
    background-color: var(--lesslight);
}

body {
    background-color: var(--light);
    margin: 0;
    max-width: 800px;
    padding: 0 20px 20px 20px;
    margin-left: auto;
    margin-right: auto;
}

header {
    padding-top: 1rem;
    text-align: center;
}

header h1 {
    font-weight: 400;
}

h3 {
    font-weight: 500;
}

h3 > small {
    opacity: .4;
    font-size: 0.8rem;
}

ul {
    padding-left: 0;
}

img {
    max-width: 100%;
    height: auto;
}

button, .button, input[type=submit] {
    display: inline-block;
    background-color: var(--dark);
    color: var(--light);
    text-align: center;
    padding: .5em;
    border-radius: .25em;
    text-decoration: none;
    border: none;
    cursor: pointer;
}

button:hover, .button:hover, input[type=submit]:hover {
    color: var(--lesslight);
    background-color: var(--moredark);
}

/* Add a margin between side-by-side buttons */
button + button, .button + .button, input[type=submit] + input[type=submit] {
    margin-left: 1em;
}

ul {
    list-style: none;
    margin: 0;
    padding: 0;
}

hr {
    border: none;
    border-top: 1px solid var(--lesslight);
}

.center {
    display: block;
    margin-left: auto;
    margin-right: auto;
    text-align: center;
}

.bordered {
    border: 3px solid;
}

.home {
    display: inline-block;
    background-color: var(--dark);
    color: var(--light);
    margin-top: 20px;
    padding: 5px 10px 5px 10px;
    text-decoration: none;
    font-weight: bold;
}

/* Desktop sizes */
@media only screen and (min-width: 600px) {
    ol.twocol {
        column-count: 2;
    }
    
    .row {
        display: flex;
        flex-direction: row;
        padding: 0;
        width: 100%;
    }

    /* Make everything in a row a column */
    .row > * {
        display: block;
        flex: 1 1 auto;
        max-width: 100%;
        width: 100%;
    }

    .row > *:not(:last-child) {
        margin-right: 10px;
    }
}

/* Dark mode overrides (confusingly inverse) */
@media (prefers-color-scheme: dark) {
    :root {
        --light: #222;
        --lesslight: #333;
        --dark: #eee;
        --moredark: #fefefe;
    }
    /* This fixes an odd blue then white shadow on FF in dark mode */
    *:focus {
        outline: var(--light);
        box-shadow: 0 0 0 .25em royalblue;
    }
}