BioHacker News | Anchoreum: A game for learning CSS anchor positioning

▲Anchoreum: A game for learning CSS anchor positioning(anchoreum.com)

87 points by thomaspark 29 days ago | 11 comments

▲culi 29 days ago

If this accepts Firefox and Safari then it could be a great addition to "intro to web dev" tutorials

CSS selectors https://flukeout.github.io/

▲lelandfe 29 days ago

Same creator as the first two, Thomas Park. Looks like he's started a series of these, but they're all paywalled except those three: https://codepip.com/games/

▲culi 28 days ago

The last one is actually independent. But you're right about the first two

▲freeCandy 29 days ago

https://caniuse.com/css-anchor-positioning

▲pinoy420 28 days ago

“No” basically. Unless it can be poly filled into safari (ios) it is not worth adopting just yet.

▲uhoh-itsmaciek 29 days ago

Neat. The museum framing is cute, and well executed with the footsteps sound between levels.

On level 20, if I set `position-try-fallbacks: flip-inline;` and drag the anchor to the top, something weird happens: the label stays on top, but is also mirrored below the anchor, except with no text or background, just a border and a translucent frame. Latest Chrome (on Ubuntu, but I don't think that matters here). Is this a Chrome bug? A bug in Anchoreum? In dev tools, it looks like it's an Anchoreum issue, because there's a separate element in the DOM.

Edit: also happens on level 25 without changing anything if I drag the anchor to the left.

Edit 2: ah, I think that area is where you're _supposed to_ place the anchor. It's not very clear from the text.

▲pinoy420 28 days ago

What do you mean by cute?

▲uhoh-itsmaciek 20 days ago

It's just a nice, playful touch.

▲nottorp 29 days ago

I suppose fixing CSS itself to be predictable would be too hard? :)

▲thibran 28 days ago

You mean like elm-ui?

https://package.elm-lang.org/packages/mdgriffith/elm-ui/late...

Fixing CSS would be nice.

▲nottorp 28 days ago

I don't know. Considering browsers are used as an application delivery platform these days, I'm not sure a library that "draws inspiration from typography" would help.

▲chilmers 29 days ago

Pretty neat. But there doesn't seem to be any way to select or style the anchored element based on which fallback position it is in? This would seem to preclude adding a directional arrow to it, which is a somewhat baseline feature for things like tooltips.

▲vollbrecht 29 days ago

Seams not supported in firefox

▲nicce 29 days ago

Nor Safari

▲webstrand 29 days ago

There's a polyfill that I haven't tried using that claims to make it work in Safari/Firefox.

▲JLCarveth 29 days ago

Great, yet another feature Firefox doesn't support... I really try to not use Chrome, but I run into this sort of issue a lot.

▲werdnapk 29 days ago

From https://caniuse.com/css-anchor-positioning you'll see "All major browser engines are working on implementing this spec.".

Not all browsers implement the same features at the same time. Firefox releases some features before Chrome, so it goes both ways.

▲nicoburns 29 days ago

Firefox is actively working on an implementation of this to be fair (source: I work on Servo and we have been accepting a steady stream of anchor positioning changes from our upstream stylo component)

▲lofaszvanitt 29 days ago

the chrome team just shovels all kinds of shit into their browser, that literally nobody uses. but it looks good in comparisons

▲layer8 28 days ago

Firefox is in good company, Safari also doesn’t.

▲somesun 26 days ago

a very good game to learn css

▲uhoh-itsmaciek 29 days ago

And no answers, huh? I'm stuck on 38.

Edit: it doesn't mention that `anchor()` can accept an anchor name, which is kind of important for this.

▲lerp-io 28 days ago

honestly idk if there is any reason anyone should be learning CSS anymore

▲MarcellusDrum 28 days ago

What's the alternative?

▲wruza 28 days ago

When will they realize that layout is fundamentally a linear problem, which only needs a "constraint" as a building block?

That all these stupid width-basis-fit-minmax-fr-anchor-span combinations boil down to "Σ(aₙxₙ) ≤ b" and a couple of specialized distributors?

How many half-assed incantations and reiterations it will take?

Jesus Christ.

▲layer8 28 days ago

What do you do when there is no solution to the set of constraints? What do you do when there are multiple (usually infinitely many) solutions to the set of constraints? More importantly, how do you specify the behavior for those cases such that all browsers behave identically? I’m not saying that CSS is better (it’s not), but it’s a bit more involved than “just run a CSP solver”, and you can still get surprising behavior depending on window size, font size, content size and so on.

▲wruza 28 days ago

What do you do when there is no solution to the set of constraints?

You break the one with the lowest priority. Then another one, until it solves. You may create groups and break whole groups (to e.g. simulate “media” “queries”).

What do you do when there are multiple (usually infinitely many) solutions to the set of constraints?

Add constraints if they are missing, or, in case you wanted it to be underconstrained, allow the mentioned distribution algos to find extremums and allocate “space” accordingly. A naively underconstrained system will solve into just something, whatever. Just like html does something when you write zero css.

More importantly, how do you specify the behavior for those cases such that all browsers behave identically?

In text? I don’t get the question. If a behavior is programmable, it is specifiable. In fact, this specification will take 100x less sentences than the current mess.

it’s a bit more involved than “just run a CSP solver”, and you can still get surprising behavior depending on window size, font size, content size and so on.

Do you have any examples? Feels like simply not true.