CSS Minecraft(benjaminaster.com)
benjaminaster.com
CSS Minecraft
https://benjaminaster.com/css-minecraft/
153 comments
have you seen this modern marvel? https://diana-adrianne.com/purecss-lace/
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.
Wow, Dark Reader absolutely mutilated her.
Wow, mobile Safari hates this. Zooming in and scrolling around crashes the page constantly.
[deleted](1)
Works fine on my iPhone 14.
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.
Scrolling is fine in Firefox but extremely slow.
It surprisingly smooth on Firefox on my Pixel 8
Interesting. Worked fine on my MBP in Safari. Even browsed around in the dev tools to see the styles used
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this is my favorite one one I've seen: https://lyra.horse/css-clicker/
These were 1852 seconds well spent. If you don't hate clickers, try this one, it was definitely made with love.
latest in my long list of poor life choices, not going to bed at 2 AM because I'm waiting to reach 10 mil views :)))))
oh man this was so perfect
that endgame is absolutely perfect
Wierd, posting the last blog post crashed firefox.
Wild, got me hooked!
I had the honor of seeing her give a talk. She also has a lot of other css projects that are awesome.
https://lynnandtonic.com/work/
Also love seeing Phoenix devs mentioned!
https://lynnandtonic.com/work/
Also love seeing Phoenix devs mentioned!
Damn, that website is great on its own and it turns out she redesigns/rewrites it every year to learn new web technologies.
https://lynnandtonic.com/archive/
Got this bookmarked to click around for inspiration in my free time.
https://lynnandtonic.com/archive/
Got this bookmarked to click around for inspiration in my free time.
So many of these look deliciously interactive but aren’t. Is that because I’m on mobile or do they not do anything?
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).
poring over it or pouring your attention :)
My bad, I forgot I'm a liquid. It's too late to edit, but s/po\w*/poured over/ anyway :)
but they are all individual divs
Hello people, author here!
Some comments on this from my side:
- You people totally overwhelmed my website... I use(d) Firebase static hosting because it's completely free and super simple, which reached the 10 GB monthly limit now. I changed to Cloudflare in the meantime, but it'll need some time for the DNS records to update. IN THE MEANTIME, PLEASE USE THE GITHUB PAGES LINK INSTEAD: https://benjaminaster.github.io/CSS-Minecraft/
- I made this almost three years ago now, to try out the limits of what's possible with pure CSS, and to test out the then-new CSS :has() selector.
- This project never got much traction until now, so I never bothered to write about how it works. Simon Willison now already wrote a blog post about it, so I guess I don't have to anymore... https://simonwillison.net/2025/May/26/css-minecraft/
- For the best experience, please view this on a desktop browser, either Chromium-based or Firefox.
- The source code is at https://github.com/BenjaminAster/CSS-Minecraft. The "index.pug" and "main.scss" files contain the actual source code; the rest is mostly just the compiled output.
- Here is a video of me building a house with it: https://www.youtube.com/watch?v=OH8-Y9frP5k
Some comments on this from my side:
- You people totally overwhelmed my website... I use(d) Firebase static hosting because it's completely free and super simple, which reached the 10 GB monthly limit now. I changed to Cloudflare in the meantime, but it'll need some time for the DNS records to update. IN THE MEANTIME, PLEASE USE THE GITHUB PAGES LINK INSTEAD: https://benjaminaster.github.io/CSS-Minecraft/
- I made this almost three years ago now, to try out the limits of what's possible with pure CSS, and to test out the then-new CSS :has() selector.
- This project never got much traction until now, so I never bothered to write about how it works. Simon Willison now already wrote a blog post about it, so I guess I don't have to anymore... https://simonwillison.net/2025/May/26/css-minecraft/
- For the best experience, please view this on a desktop browser, either Chromium-based or Firefox.
- The source code is at https://github.com/BenjaminAster/CSS-Minecraft. The "index.pug" and "main.scss" files contain the actual source code; the rest is mostly just the compiled output.
- Here is a video of me building a house with it: https://www.youtube.com/watch?v=OH8-Y9frP5k
This was criminally underrated, great job
This is fiendishly clever, and really quite elegant.
I made some of my own notes on how this works here: https://simonwillison.net/2025/May/26/css-minecraft/
I made some of my own notes on how this works here: https://simonwillison.net/2025/May/26/css-minecraft/
This is how CSS CAPTCHAs are made (for Tor websites), and sign up / login modals, and many other stuff.
good write up, thanks. talk about a combinatorial explosion!
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But highly impractical and far beyond what CSS should be used for.
Obviously...
That's why it was done
For fun and to see whether it could be done
That's why it was done
For fun and to see whether it could be done
My point is that there will be too many who will look at this and start using CSS in ways it is not intended. Even today, far too many people attempt to use CSS for things best left for SVG.
These sorts of CSS experiments have been around for as long as CSS. There even used to be a site where an entire community would take basic markup and use CSS to turn it into something else.
(I just googled that phrase - the site is CSS Zen Garden. It’s impressive Google found it because that was a bad search.)
Some people did create monstrosities, others learned the limits of CSS and used that knowledge to advance CSS. So my point is that I believe in the ability of people to advance through discovering all the things they shouldn’t do.
(I just googled that phrase - the site is CSS Zen Garden. It’s impressive Google found it because that was a bad search.)
Some people did create monstrosities, others learned the limits of CSS and used that knowledge to advance CSS. So my point is that I believe in the ability of people to advance through discovering all the things they shouldn’t do.
CSS Zen Garden is not an experiment as shown in the title of this post. The Garden shows how CSS can style the HTML elements in many different ways but it is not there to create or manipulate images as shown in the subject of this post.
That said, I have not looked at the Garden in many years so if you fine one, then you found .... one ... and I loop back to my original comment: that such things are impractical, it's not what CSS is for, and should be avoided.
That said, I have not looked at the Garden in many years so if you fine one, then you found .... one ... and I loop back to my original comment: that such things are impractical, it's not what CSS is for, and should be avoided.
In other words, you don’t learn through experimentation and your learning style is the only valid one? Okay…this isn’t worth debating but science has proven that to be wrong.
It may be worth reading some cognitive psych.
It may be worth reading some cognitive psych.
This is basically the same take as "violent videogames cause school shootings"
CSS Minecraft, or CSS CAPTCHAs, or sign up / login modals cannot be done via SVG. This is needed for JS-less websites (e.g. Tor). CSS with HTML is perfect for this use-case.
If anything these tricks enable people to build stuff without JS.
I'm still here waiting for someone at W3C to get their stuff together and provide a spec for something that could enable an accessible hamburger menu with plain HTML + CSS.
Or a sane details element that DOES NOT REQUIRE JS TO CHANGE STATE (without interaction). Jesus.
I'm still here waiting for someone at W3C to get their stuff together and provide a spec for something that could enable an accessible hamburger menu with plain HTML + CSS.
Or a sane details element that DOES NOT REQUIRE JS TO CHANGE STATE (without interaction). Jesus.
If you really wanna get your blood boiling how about some Doom with HTML checkboxes - https://healeycodes.com/doom-rendered-via-checkboxes
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.
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.
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.
I kind of like it.
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.
That is the most hacky solution I may have ever seen in a CSS demo. I love it.
It's always radio buttons, every single time
Incredibly brilliant. Seems to have gone completely unnoticed 2.5 years ago.
https://news.ycombinator.com/item?id=33579407
https://news.ycombinator.com/item?id=33579407
See now that's amazing. Luck is such a factor in ... everything!
Another hug of death. The website says "It must be upgraded via the Firebase console before it can begin serving traffic again."
Wayback machine for when it used to work: https://web.archive.org/web/20250317122419/https://benjamina...
Wayback machine for when it used to work: https://web.archive.org/web/20250317122419/https://benjamina...
Makes you wonder, how many webpages are dependant on such services. The Web has always been brittle, but it's a little sad seeing a website not able to survive ~50k users on its first day online.
Even the least offenders, GitHub Pages, broke links before [0].
[0]: https://github.blog/news-insights/product-news/new-github-pa...
Even the least offenders, GitHub Pages, broke links before [0].
[0]: https://github.blog/news-insights/product-news/new-github-pa...
Best anti-firebase post I've ever seen
Yah, I hope this doesn't end up costing them an arm and a leg :( it was working last night
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this project doesn't use a backend, so not sure why firebase is needed. github pages would have unlimited bandwidth.
Alternative URL for if the site has trouble keeping up: https://benjaminaster.github.io/CSS-Minecraft/
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.
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.
Is this a thing? https://medium.com/hypersphere-codes/randomness-in-css-b55a0...
Unfortunately that solution does not work on Firefox or Safari.
you can pretty easily get randomness for clickable stuff by animating the z-index of multiple objects
Interesting! I'm not familiar with this approach and look forward to trying it. Do you think it can be used to set a var that can be used for generative colors?
Can LLMs help?
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.
To answer your question, LLMs confirm you can't generate a random number in CSS.
alas, it seems that just shouting "AI" at problems is the latest trend in people who don't build software acting as though they know how building software works.
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
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".
I really like doing this when something extraordinary happens by "accident".
Reminds me of a couple of Keith Clark's projects from a good 10+ years back
https://keithclark.co.uk/labs/css-fps/desktop/
https://keithclark.co.uk/labs/css-3d-shadows/
https://keithclark.co.uk/labs/css-fps/desktop/
https://keithclark.co.uk/labs/css-3d-shadows/
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.
https://github.com/BenjaminAster/CSS-Minecraft/blob/main/mai...
https://github.com/BenjaminAster/CSS-Minecraft/blob/main/mai...
I got "Bandwidth Quota Exceeded"
It also works on the web archive.
https://web.archive.org/web/20250317122419/https://benjamina...
https://web.archive.org/web/20250317122419/https://benjamina...
Same, maybe shouldn't go with the serverless hype.. It's a static website after all :D
Get the archive from github and load it locally: https://github.com/BenjaminAster/CSS-Minecraft/archive/refs/...
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!
Is pug doing something special here that another template engine, or just a custom script, could not do?
Concatenating strings is not that complicated.
Concatenating strings is not that complicated.
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.
And it's only 480 lines of CSS! https://github.com/BenjaminAster/CSS-Minecraft/blob/main/mai...
... and 46,022 lines of HTML (3.07MB)
... and 46,022 lines of HTML (3.07MB)
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.
It’s extremely impressive, but it’s not “Quake”; it’s only the difficulty selection hallway from Quake. No enemies.
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!
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!
Note: the <input> tag does not use and does not need a closing slash and never has in any HTML specification.
https://html.spec.whatwg.org/dev/input.html#the-input-elemen...
https://html.spec.whatwg.org/dev/input.html#the-input-elemen...
It's sometimes done to make the same markup compatible with XHTML, without harming its interpretation in HTML.
You are either running XHTML or you are not. No need to carry any compatibility overhead. I doubt he is serving XHTML.
I personally prefer <input /> if only to stop other developers to not try doing <input>content </input>.
There are other tags you can omit the closing tag but yet the opening tag shouldn’t be self-closed.
<ol>
<li>one
<li>two
</ol>
I know that, but many developers don't. I can't wait to see the confusion on why my tag didn't auto-close like a <li> tag.
Ambiguity can be a dangerous thing, and not closing HTML tags can be a cause of that in my experience.
Ambiguity can be a dangerous thing, and not closing HTML tags can be a cause of that in my experience.
The term for such "other developers" is "hobbyists".
There are other terms but I won't list them here.
There are other terms but I won't list them here.
Sometimes "other developers" is also "coworkers".
I've found less ambiguity to be a better thing than not, where possible. Self-closing a tag that can't contain anything is one such example of removing ambiguity for "hobbyists".
I've found less ambiguity to be a better thing than not, where possible. Self-closing a tag that can't contain anything is one such example of removing ambiguity for "hobbyists".
One would need to know the tag is self-closing in order to put the closing slash in. Right? So if one knows it's self-closing already, why do they need to add the extra weight?
Makes no sense.
If one wants to add content to a self-closing element, one has far more problems than we're talking about here.
Makes no sense.
If one wants to add content to a self-closing element, one has far more problems than we're talking about here.
It can be done by libraries, for example, which want their output to be valid in both HTML and XHTML.
Note that's it's not a syntax error in HTML - because HTML doesn't have syntax errors. The HTML5 spec tried to codify all the weird Postel's law quirks of existing HTML4 parsers, and in this case, tells you how to ignore the extra / if you're a parser. Nothing is a syntax error.
Note that's it's not a syntax error in HTML - because HTML doesn't have syntax errors. The HTML5 spec tried to codify all the weird Postel's law quirks of existing HTML4 parsers, and in this case, tells you how to ignore the extra / if you're a parser. Nothing is a syntax error.
I didn't say it's a syntax error. I said it is not specified in the standard. You can put the slash there but it has no meaning, it does nothing, and browsers ignore it. If anything, it can cause problems: https://github.com/validator/validator/wiki/Markup-%C2%BB-Vo...
So it's best to not do it altogether. If one thinks they need to be compliant with both HTML and XHTML, I'd bet they have far more problems with the rest of their markup that would fail at such an effort.
So it's best to not do it altogether. If one thinks they need to be compliant with both HTML and XHTML, I'd bet they have far more problems with the rest of their markup that would fail at such an effort.
> If one wants to add content to a self-closing element, one has far more problems than we're talking about here.
Yes.
Yes.
Another impressive CSS creation -- CSS Puzzle Box: https://suricrasia.online/puzzlebox/
Damn, just visiting this site makes me want to reinstall Minecraft haha.
Did anyone else involuntarily let out multiple expletives when they saw it and it dawned on them how hard this must have been?
This is insane to me.
This is insane to me.
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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.
I also got "Bandwidth Quota Exceeded". Seems like you're doing well!
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!
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!
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.
My one regret in life is not having seen this before your Firebase credits were spent for the month. Looking forward to a June attempt!
View it on GitHub Pages instead ;)
https://benjaminaster.github.io/CSS-Minecraft/
Web-based minecraft, when?
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:
https://classic.minecraft.net/
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/
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
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
Is your repo still available?
Yup! Though I haven't touched it in several years:
https://github.com/fenomas/noa
https://github.com/fenomas/noa
You used to be able to play Minecraft classic directly on minecraft.net
It still exists at https://classic.minecraft.net/
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.
https://en.wikipedia.org/wiki/Minecraft
>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
[deleted]
Wow! I had no idea, it even supports up to 9 additional players.
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.
The full java version of the game was ported to webassembly/webgl a while ago. It's called eaglercraft: https://eaglercraft.com
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.)
Minecraft these days is missing a lot of what people would consider "Minecraft" 8 years 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.
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.
It got extended, embraced and extinguished.
Nope, still exists :3 https://classic.minecraft.net/
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.
this is pretty empty
The phone is ringing—Java Applets called B-)
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This is breathtaking and embodiment of creativity.
Truly a legend!
Doing this art just with css ,you are greatest one in css sir.
Damn, this is impressive.
Very impressive
Chuối
Mind blowing
Brilliant !
Gj
that's amazing!!!
That's crazy
Well done!
I wonder when AIs can write clever codes like this. Given a surprising constraint.
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 find a CAPTCHA like this in use for the Tor variant of Reddit (?).
> 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.
[1] https://developer.mozilla.org/en-US/docs/Web/API/CSS_Paintin...
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...
> 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?
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?
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/