First CSS rule not loading into browser

Hi, I have encountered a bizarre issue where the first CSS rule in a style sheet is not loading into the browser. All rules after the first load normally.

I have been having this issue for a few days, and recreating the style sheet does not fix it.

For example, the rule sim-intro below does not load here:

If I move the same CSS into the WordPress Customizer, it loads normally. I have attached an export of the Tangible style sheet if useful.

What could cause this unusual behaviour? Thanks.

/* Typography - Intro */
.sim-intro {
    width: 800px;
    padding: 10px;
    margin: auto;
.sim-intro p {
    font-size: 1rem;
    line-height: 1.8;
    text-align: center;
@media only screen and (min-width: 769px) {
    .sim-intro p {
        font-size: 1.5rem;

Hmm, that’s odd. Does this behaviour happen on a fresh WP install for you? I just tried it on my end and the sim-intro rule seems to be showing up as I’d expect.

Edit: one of my colleagues was able to replicate this so I’ll have them report the bug and we’ll check back in here with an update.

Thanks for that. I do seem to find obscure bugs. The workaround is to simply add another rule to the top of the sheet.