The demo itself is a straight up fork from the aforementioned HTML Tags Memory Test with an adjusted list of items to guess and a small style change to tweak the appearance of the already guessed results.
The list of itself properties was generated from the “Properties and Descriptors” CSS Index. The index lists 705 properties, but I’ve filtered out -webkit-prefixed properties that also exist without such a prefix. The filtered array was eventually converted to a string and base64 encoded to discourage cheating.
// Get all listed properties
const allProps = $$('#properties + div > ul.index > li').map(($li) => $li.textContent.trim().split("\n")); // ~> 705 props
// Filter out -webkit prefixed props that also exist without a prefix
const filteredProps = allProps.filter(prop => !(prop.startsWith('-webkit-') && allProps.includes(prop.replace('-webkit-', '')))); // ~> 650 props
// Base64 encode the whole lot string to discourage cheating ;)
const encodedProps = btoa(filteredProps.join(','));
Note that when decoded again there are 653 properties to guess. That’s because one of the entries lists 4 properties separated by a comma.
🔥 Like what you see? Want to stay in the loop? Here's how:
Having played and enjoyed the original Half-Life when it first came out (way back in 1998), I must say I’m quite looking forward to “Half-Life: Alyx”:
And oh, don’t be confused about moving-part in the game: shown above is teleport mode. There are two other modes you can use: shift (= smooth zoom, as shown in this video) and continuous (= move using an analogue stick, as shown in this video).