Load the static fonts as a fallback

dabblet.css

body {
  font-family: 'Venn VF', 'Venn', sans-serif;
}

@supports (font-variation-settings: normal) {
  @font-face {
    font-family: 'Venn VF';
    src: url('https://s3-us-west-2.amazonaws.com/s.cdpn.io/814870/Venn_VF.woff2') format('woff2-variations'), /* for Safari */
          url('https://s3-us-west-2.amazonaws.com/s.cdpn.io/814870/Venn_VF.woff2') format('woff2'); /* for all other supporting browsers */
    font-display: fallback;
    font-weight: 300 800; /* prevents faux bolding in Safari */
    font-stretch: 75 125;
  }
}

/* Load the static fonts as a fallback */
@font-face {
    font-family: 'Venn';
    src: url('https://s3-us-west-2.amazonaws.com/s.cdpn.io/814870/Venn_Regular.woff2') format('woff2');
    font-display: fallback; /* has nothing to do with the fact that this is the fallback font */
}

@font-face {
    font-family: 'Venn';
    src: url('https://s3-us-west-2.amazonaws.com/s.cdpn.io/814870/Venn_Bold.woff2') format('woff2');
    font-display: fallback; /* has nothing to do with the fact that this is the fallback font */
    font-weight: 700;
}

dabblet.html

<p>Hello, <strong>world</strong>!</p>

dabblet.js

// alert('Hello world!');

settings.json

{"view":"split","fontsize":"100","seethrough":"","prefixfree":"1","page":"css"}