Louis Lazaris breaks down some bonafide CSS trickery from Jane. The Pen shows off interactivity where:
- You have to press a special combination of keys on a keyboard.
- Then type a secret password.
From there, a special message pops up on the screen. Easily JavaScript territory, but no, this is done here entirely in HTML and CSS, which is wild.
A lot of little known features and tricks is combined here to pull this off, like HTML’s accesskey and pattern attributes, as well as :not(), :placeholder-shown, and :valid in CSS—not to mention the custom property toggle trick.
That’s… wow. And yet, look how very little code it is.
Note: on Firefox (Windows), you need to use Alt-Shift-C