Incredible. I was so skeptical that I went in on the neckruff and from there to a lacetop, it's really all generated based on background-image but without using images but gradients of specific colors, as well as box-shadows and the like.
ryukoposting · 10h ago
Wow, Dark Reader absolutely mutilated her.
lelandfe · 11h ago
Wow, mobile Safari hates this. Zooming in and scrolling around crashes the page constantly.
reaperducer · 11h ago
Works fine on my iPhone 14.
lelandfe · 10h ago
Similar problems on my MBP, actually – just sans crashed tab. Zooming in and scrolling around on Chrome and Safari cause the divs to rerender (repaint?) and often not all of them even do! E.g. Chrome: https://imgur.com/a/VWCAL9G
Scrolling is fine in Firefox but extremely slow.
yonatan8070 · 9h ago
It surprisingly smooth on Firefox on my Pixel 8
asimovDev · 8h ago
Interesting. Worked fine on my MBP in Safari. Even browsed around in the dev tools to see the styles used
So many of these look deliciously interactive but aren’t. Is that because I’m on mobile or do they not do anything?
gs17 · 12h ago
I don't think any on the first page are interactive. There might be a few on the next page of it (I only found one where a pen changes color on hover).
matrix2596 · 5h ago
poring over it or pouring your attention :)
simonw · 13h ago
This is fiendishly clever, and really quite elegant.
If anyone's wondering how it manages the state, a quick peek into the source code shows that it uses radiobuttons and the HTML contains all the blocks you could ever possibly place.
johnh-hn · 15h ago
If anyone is equally curious how the camera state works, it looks like the camera is controlled by running animations when a button is in its :active state and pausing them otherwise.
movedx01 · 16m ago
It's always radio buttons, every single time
globie · 15h ago
I... you're right. I was wondering why the world was only 9x9x9, there's 46k lines showing each block can have air, stone, grass, dirt, log, wood, leaves, or glass.
I kind of like it.
donatj · 2h ago
Radio buttons and checkboxes really are magic when it comes to doing neat things in pure CSS. We used to have a lot of neat stuff like pure html/css tabs and toggles but they didn't pass an accessibility audit.
90s_dev · 15h ago
That is the most hacky solution I may have ever seen in a CSS demo. I love it.
Truly incredible from an HTML perspective, but I think also a testament to how catchy and simple Minecraft is as a concept... a few minutes of noodling around in here and I already built myself a cute little tree and a hill: https://i.imgur.com/PjlDWo5.png
patates · 6h ago
Just think about setting what Minecraft has achieved as requirements from the get go: 1) Be one of the most successful games ever created. 2) Basic game mechanics should be possible to be implemented via just HTML and CSS (no JS).
I really like doing this when something extraordinary happens by "accident".
It's absolutely brilliant how rotation and movement control is achieved by changing the animation-play-state value using the :active pseudo-class on button elements.
Pug is an unsung hero in this demo. The template engine made it possible to brute force the UI with 4 levels of nested loop. Impressive!
tantalor · 50m ago
Is pug doing something special here that another template engine, or just a custom script, could not do?
Concatenating strings is not that complicated.
perilunar · 3m ago
You could write a script in JS to generate all the elements, then save the rendered HTML. Bootstrapping a HTML+CSS only site with HTML+CSS+JS.
bradly · 13h ago
Very impressive!
As I've hit my mid-life slide and (regressed|progressed) back to my youth-self, I've found myself just writing a bunch of apps and sites in html and css and really enjoying it.
One thing I still would like to see cracked is a random-like number in pure CSS. You can almost us there with some of the math functions and browser attributes, but I haven't found anything reliable.
Can they? I think it's weird that you ask a question (or, offer a possible solution in the shape of a question) without verifying your own assertion first.
To answer your question, LLMs confirm you can't generate a random number in CSS.
felineflock · 15h ago
Please tell me if I understood it correctly:
It implements voxels via <input type="radio" />.
Each of the faces of each voxel is configured via <label>s, one for each face having a different CSS class.
There is a voxel for each type of block (dirt, grass, stone, etc) and only one is activated at a time.
The <input>s are arranged in a 9x9 grid 10 blocks tall times the number of different types of blocks (about 6500 total).
All that is enclosed with <div>s with CSS classes that respond to the camera navigation (look up/down, move up/down, forward/back, clockwise/counter)
That is brilliant!
assimpleaspossi · 5h ago
Note: the <input> tag does not use and does not need a closing slash and never has in any HTML specification.
Blew my mind. I have hundreds of tabs open, no issue on linux chrome.
echoangle · 15h ago
I think at some point the number of tabs doesn't matter because the tab is unloaded and the state is maybe stored on disk. As long as you don't open them, having them open shouldn't slow the browser down.
ddtaylor · 2h ago
I remember discovering this trick nearly two decades ago. A co-worker and myself were a bit puzzled at the time and we kind of tossed the idea in the air that "doesn't this mean CSS is Turing Complete?" but we moved on to making things work on IE6 for old clients.
voodooEntity · 4h ago
Very nice work :) especially that you even support building sideways and the "hover" always is perfectly placed. Thats something that amazes me the most how clean it feels to place a block. Very good job!
anil_gr · 40m ago
Brilliant !
khurdula · 13h ago
Damn, just visiting this site makes me want to reinstall Minecraft haha.
Recently I came across Quake implemented within a single WebGL shader (https://www.shadertoy.com/view/lsKfWd), but this is another level. HTML/CSS is a programming language now.
teddyh · 57m ago
It’s extremely impressive, but it’s not “Quake”; it’s only the difficulty selection hallway from Quake. No enemies.
est · 4h ago
I wonder when AIs can write clever codes like this. Given a surprising constraint.
johnisgood · 57m ago
About a year ago I tried to make GPT give me a CAPTCHA using the same method and it failed (even after helping it quite a lot). I don't know how it would fare now. You can see find a CAPTCHA like this in use for the Tor variant of Reddit (?).
cod3rboy · 11h ago
This is breathtaking and embodiment of creativity.
Truly a legend!
justinde · 14h ago
Web-based minecraft, when?
fenomas · 12h ago
Only guessing, but I have a theory that Mojang considered that circa 2017 :D
In 2019 they released a web version of minecraft classic, as a quirky marketing thing for the game's anniversary. But what they released turned out to be built on my open-source voxel engine, and when I dug around their code I realized they'd yoinked my engine a solid two years earlier.
And the demo they released was probably not two year's of work, so my theory is that somebody at Mojang investigated the idea of minecraft-but-JS, and made a demo but then decided not to pursue it, and then later on it got recycled for the marketing demo. (which, annoyingly for me, they pretended was an old alpha build of Minecraft instead of a new thing built on open source.)
The demo is still live, though the multiplayer stopped working the same day it launched:
Humorous postscript, btw: two months after Mojang forked my voxel engine, somebody left an anonymous "this is awful, you are a terrible programmer" comment on the engine repo.
It's probably a total coincidence, but I like to imagine that the comment came from somebody at Mojang, and that my awful code is the reason why minecraft isn't a web app today :D
BtM909 · 2h ago
Is your repo still available?
fenomas · 1h ago
Yup! Though I haven't touched it in several years:
I was confused because I thought Minecraft was originally Java, but that is Javascript. Wikipedia explains:
>On 7 May, 2019, coinciding with Minecraft's 10th anniversary, a JavaScript recreation of an old 2009 Java Edition build named Minecraft Classic was made available to play online for free.
The full game was available on minecraft.net for many years. At times it was the only way to play multiplayer when the authentication server would go down.
beeflet · 9h ago
The full java version of the game was ported to webassembly/webgl a while ago. It's called eaglercraft: https://eaglercraft.com
zimpenfish · 5h ago
Minor nit - "the full java version of an at-least 8 years old release" (which is necessarily missing -a lot- of what people would consider "Minecraft" these days.)
immibis · 4h ago
Minecraft these days is missing a lot of what people would consider "Minecraft" 8 years ago.
sparky_ · 2h ago
I don't get it - isn't this blatant copyright infringement? Seems like they're just running some kind of cracked Minecraft build with a JVM-in-JS layer or some such trickery?
auxiliarymoose · 14h ago
The phone is ringing—Java Applets called B-)
thrance · 14h ago
Fun fact: one of the first versions of Minecraft (the "classic" one) was playable in a web browser. I actually did play it as a young teen and later thought I must have dreamt it, when I couldn't find it anywhere.
rbits · 11h ago
Yeah I remember that. I think it was back in version 1.6 or something. It kinda blew my mind as a kid playing a full-on computer game in a browser.
Not "still". That is not the same game that was on the website when I first got into Minecraft in 2010 but a JavaScript recreation made in 2019.
make3 · 11h ago
this is pretty empty
kazarka · 6h ago
Gj
zizomod · 11h ago
Doing this art just with css ,you are greatest one in css sir.
sefke · 15h ago
Damn, this is impressive.
dylanhouli · 10h ago
Mind blowing
h1fra · 15h ago
Very impressive
bpiroman · 11h ago
that's amazing!!!
quantadev · 15h ago
Pretty slick! I never had played minecraft before. I never knew how blocks were place down until I ran this page. But it needs to be able to use the mouse to rotate, and mouse-wheel to scale!
terribleperson · 10h ago
When playing the actual game, your viewpoint moves with the character, moved by the WASD keys and oriented with the mouse. You can only ever place one block at a time, though.
ryanisnan · 15h ago
Well done!
zizomod · 11h ago
That's crazy
90s_dev · 16h ago
> For the best performance, please close other tabs and running programs.
This has always been the case with CSS, hasn't it? When you use it for rendering something relatively complex, you're kinda doomed.
I get the dream, we want everything to be declarative, and leave room for future optimizations, so that we can write once and run everywhere forever.
But in practice, it's not really an improvement over traditional GUIs that let you draw directly. Hence CSS is literally adding draw[1].
This is a huge reason 90s.dev doesn't use HTML/CSS but starts from scratch and lets you draw right into WebGL2 yourself, or with high-level APIs if you want.
> When you use it for rendering something relatively complex, you're kinda doomed.
Can you describe a time that happened to you, and why you felt doomed?
That doesn’t like something that a person who has really used CSS in any meaningful way would say. Sharp edges, sure, but what technology doesn’t have that?
None4U · 12h ago
The game https://corru.observer/ is a great example of a CSS-rendered 3D video game that runs fairly well on modern devices (even playable on mobile although it'll try to block you based on viewport size if you're not in "desktop mode")
This immediately brought "A Single Div"[0] to mind, which stood as the coolest CSS demo I'd seen for... 11 years!
This one takes the cake. I'll be pouring over it. Thanks!
[0]: https://a.singlediv.com/
Scrolling is fine in Firefox but extremely slow.
I made some of my own notes on how this works here: https://simonwillison.net/2025/May/26/css-minecraft/
That's why it was done
For fun and to see whether it could be done
I kind of like it.
https://news.ycombinator.com/item?id=33579407
https://keithclark.co.uk/labs/css-fps/desktop/
https://keithclark.co.uk/labs/css-3d-shadows/
I really like doing this when something extraordinary happens by "accident".
https://github.com/BenjaminAster/CSS-Minecraft/blob/main/mai...
Concatenating strings is not that complicated.
As I've hit my mid-life slide and (regressed|progressed) back to my youth-self, I've found myself just writing a bunch of apps and sites in html and css and really enjoying it.
One thing I still would like to see cracked is a random-like number in pure CSS. You can almost us there with some of the math functions and browser attributes, but I haven't found anything reliable.
To answer your question, LLMs confirm you can't generate a random number in CSS.
It implements voxels via <input type="radio" />.
Each of the faces of each voxel is configured via <label>s, one for each face having a different CSS class.
There is a voxel for each type of block (dirt, grass, stone, etc) and only one is activated at a time.
The <input>s are arranged in a 9x9 grid 10 blocks tall times the number of different types of blocks (about 6500 total).
All that is enclosed with <div>s with CSS classes that respond to the camera navigation (look up/down, move up/down, forward/back, clockwise/counter)
That is brilliant!
https://html.spec.whatwg.org/dev/input.html#the-input-elemen...
... and 46,022 lines of HTML (3.07MB)
In 2019 they released a web version of minecraft classic, as a quirky marketing thing for the game's anniversary. But what they released turned out to be built on my open-source voxel engine, and when I dug around their code I realized they'd yoinked my engine a solid two years earlier.
And the demo they released was probably not two year's of work, so my theory is that somebody at Mojang investigated the idea of minecraft-but-JS, and made a demo but then decided not to pursue it, and then later on it got recycled for the marketing demo. (which, annoyingly for me, they pretended was an old alpha build of Minecraft instead of a new thing built on open source.)
The demo is still live, though the multiplayer stopped working the same day it launched:
https://classic.minecraft.net/
It's probably a total coincidence, but I like to imagine that the comment came from somebody at Mojang, and that my awful code is the reason why minecraft isn't a web app today :D
https://github.com/fenomas/noa
>On 7 May, 2019, coinciding with Minecraft's 10th anniversary, a JavaScript recreation of an old 2009 Java Edition build named Minecraft Classic was made available to play online for free.
https://en.wikipedia.org/wiki/Minecraft
No comments yet
This has always been the case with CSS, hasn't it? When you use it for rendering something relatively complex, you're kinda doomed.
I get the dream, we want everything to be declarative, and leave room for future optimizations, so that we can write once and run everywhere forever.
But in practice, it's not really an improvement over traditional GUIs that let you draw directly. Hence CSS is literally adding draw[1].
This is a huge reason 90s.dev doesn't use HTML/CSS but starts from scratch and lets you draw right into WebGL2 yourself, or with high-level APIs if you want.
[1] https://developer.mozilla.org/en-US/docs/Web/API/CSS_Paintin...
Can you describe a time that happened to you, and why you felt doomed?
That doesn’t like something that a person who has really used CSS in any meaningful way would say. Sharp edges, sure, but what technology doesn’t have that?