">
    <link rel="help" href="https://www.w3.org/TR/css-flexbox-1/#hypothetical-main-size">
    <link rel="help" href="https://www.w3.org/TR/css-flexbox-1/#hypothetical-cross-size">
    <style>
      .flexbox {
        display: flex;
        flex-direction: row;
        border: 1px solid black;
        margin: 0 2px 2px 0; /* (Just for spacing things out, visually) */
        width: 40px;
        height: 40px;

        justify-content: flex-start;
        align-items: flex-start;

        float: left; /* Fo