Oh, and to be fair, browser compatibility is where the real pain the booty comes in. Unfortunately, most browser makers (cough, cough Microsoft) hate following standards. Was even worse in the past when there was no standards committee as everyone was fighting for web dominance. But, thank God it's much better these days. Anywho, the site `Can I Use` will be your new BFF for web development as it'll list browser compatibility. You can automate all of this of course if you have a proper dev environment set up in Node, but for a quick check it's still a great site to know. Here, I'm checking to see which browsers support viewport units like `100vh`. So, they've been around for about 10 years now, which makes them pretty safe to rely on with this. For people with an old browser that doesn't support flexbox or viewport units, it just won't span the entire viewport unless there's content. No biggie. Site still works. [Viewport units: vw, vh, vmin, vmax | Can I use... Support tables for HTML5, CSS3, etc](https://caniuse.com/viewport-units)
Jeremy Falcon