small hint for getting to that 121: What if you could move an element by a quarter of a …?<\/p><\/blockquote>\n
Attempts 5 and 6: 122 bytes<\/h4>\n tag costs extra bytes.
You may have noticed that we used 5in for the spread in our last box shadow. Playing with weird units is a huge part of CSS golfing. In this case, we just need the shadow to cover the 400×300 canvas and ‘5in‘ (480px) is shorter than any pixel value.
Attempt 2: 141 bytes
<p style="margin:75"></p>
This introduces a pretty important golfing trick: replacing spaces with plus signs allows us to remove the quotes around attributes, saving a couple bytes. I’m not totally sure why this works. Someone suggested it may be related to this part of the HTML spec. If you have a better answer, please let me know!
This attempt also cleans up a couple of whitespace mistakes from the last attempt.
Attempt 3: 126 bytes
Using a
tag instead of a means that:
- We no longer spend bytes setting height or width on a paragraph
- We get access to bgcolor
You may have noticed that we used 5in for the spread in our last box shadow. Playing with weird units is a huge part of CSS golfing. In this case, we just need the shadow to cover the 400×300 canvas and ‘5in‘ (480px) is shorter than any pixel value.
Attempt 2: 141 bytes
<p style="margin:75"></p>
This introduces a pretty important golfing trick: replacing spaces with plus signs allows us to remove the quotes around attributes, saving a couple bytes. I’m not totally sure why this works. Someone suggested it may be related to this part of the HTML spec. If you have a better answer, please let me know!
This attempt also cleans up a couple of whitespace mistakes from the last attempt.
Attempt 3: 126 bytes
Using a
tag instead of ameans that:
bgcolor is a deprecated attribute that comes up often in CSS golf solutions. It only works on a few tags (
included), and does two great things:- Saves us from spending bytes on “background:“
- Saves us a byte by allowing us to omit # in hex colors. Additionally, if a color ends in one or two zeros, we can remove them and it will still render correctly. For example, FFFF00 is the same as FFFF.
There’s a golf regression in this iteration! Can you spot it?
The “border” method
By this point, I had spent quite a few hours tinkering on and off with this target and was getting pretty stuck. Fortunately, CSSBattle has a friendly community on Spectrum that is more than willing to lend a hand.
At the time, Praveen held the #1 spot with two bytes fewer than I had managed, so I asked for some help. He suggested leveraging both the
and elements to position everything while using borders in place of a background color.Attempt 4: 126 bytes
<style>*{border-radius:67% 0;border:75px solid#F3AC3C;margin:0 50;box-shadow:-50px 0#998235,-100px 0#1A4341,0 0 0 5in#0B2429</style>
This is a pretty huge departure from our last strategy. Our body tag is gone and we’re using
This was tough for me to grok, but Praveen made a diagram that explains things pretty well. Here’s a prettied up version:
a and b are the margin and border on , and c is the margin on
. The right margin on doesn’t do anything since there’s no room to push the to the left and it already has zero width.Once our box shadows are applied, b is covered up and all that’s left is our target image.
There are still some optimizations missing here though. Dorus van den Oord was able to take the border method down to a lean 121 bytes, offering this cryptic bit of advice:
small hint for getting to that 121: What if you could move an element by a quarter of a …?
Attempts 5 and 6: 122 bytes
<style>*{border-radius:67% 0;border:75px solid#F3AC3C;margin:0 50;box-shadow:-53q 0#998235,-25vw 0#1A4341,0 0 0 5in#0B2429</style>
Turns out all we needed was a unit hardly anyone’s ever heard of (q) (and the humble vw). Having to write “px” is rarely correct in CSS golf, so it’s something to be on the lookout for. Here, we can replace 100px with 25vw and 50px with 53q.
A q, or quarter-millimeter, is exactly that — 1/4th of a millimeter, or just under a pixel. The q unit is a staple of CSS golf as one of two values (the other being %) that require just one byte to express. I’ve combined my 5th and 6th attempts here since both were just unit tweaks. We’re still a byte off from 121 though!
Attempt 7: 121 bytes
<style>*{border-radius:67%0;border:75px solid#F3AC3C;margin:0 50;box-shadow:-53q 0#998235,-25vw 0#1A4341,0 0 0 5in#0B2429</style>
We finally fixed that regression from the third attempt, thanks to a pull request from Praveen. A percentage doesn’t need a space between it and subsequent values, so we can save a byte in our border-radius. This is a great example of how sharing code can help everyone involved. I had been stuck on this for a pretty dang long time.
The “funky margin” method
Borders aren’t the only approach, though! Enter Rasmus Fl?e’s funky margin:
I got 123 chars on #7 by using box-shadow and a funky margin:75 400 75-150 :)
Attempt 8: 120 bytes
Here’s how this works, as Rasmus explains it:
positive right margin pushes it off canvas to the left — and negative left margin stretches the element to the wanted width :)
Here it is drawn out:
The right margin (b) pushes the
element all the way to the left, collapsing it to zero width. The negative left margin (a) then stretches it back to 150px wide (the width of the leaf shape), and then our box shadow (c) is offset enough to be in view. This is awesome because we no longer have to deal with negative box shadows in order to get everything to layer correctly.We’re also back to bgcolor and get to leverage a nice quirk of background colors: because doesn’t have its own background color, it inherits one from
.Attempts 9 and 10: 118 bytes
With a bit more unit-wrangling we’re able to save ourselves two more bytes (props to Dorus, who was the first to discover this optimization). Adjusting the margins saves a digit (150 becomes 90), and, as a sweet bonus, we get to convert 86mm to 70mm, which becomes 7cm. I’ve again combined two attempts here which were minor unit fixes. (I’m embarrassed to say I initially missed the mm–cm conversion.)
Attempt 11: 117 bytes
Romain Deltour was the first to find this 117-byte solution. Changing 340 to 85% means we get to omit a space after one of our values (just like we did with border-radius), saving another byte.
Attempt 12: 115 bytes
Two full weeks after Romain’s 117-byte solution, Viacheslav Popov was able to alpha composite his way to 115 bytes via 4-digit hex codes.
I really love this because — not only is it dang clever — but a lot of people (myself included) thought the target had already been fully optimized. Viacheslav’s persistence both sparked a new round of discussion and added another CSS-Trick? to our arsenal for future targets.
Attempt 13:
This seems awfully close to optimal to me but that certainly doesn’t mean it can’t be beat — why not give it a shot? There’s prior art to get you started, plenty of folks willing to help, and even some tooling. Happy golfing ??
The above is the detailed content of A CSS Golfing Exercise. For more information, please follow other related articles on the PHP Chinese website!
Hot AI Tools
Undress AI Tool
Undress images for free
Undresser.AI Undress
AI-powered app for creating realistic nude photos
AI Clothes Remover
Online AI tool for removing clothes from photos.
Clothoff.io
AI clothes remover
Video Face Swap
Swap faces in any video effortlessly with our completely free AI face swap tool!
Hot Article
Hot Tools
Notepad++7.3.1
Easy-to-use and free code editor
SublimeText3 Chinese version
Chinese version, very easy to use
Zend Studio 13.0.1
Powerful PHP integrated development environment
Dreamweaver CS6
Visual web development tools
SublimeText3 Mac version
God-level code editing software (SublimeText3)
Hot Topics
What is 'render-blocking CSS'?
Jun 24, 2025 am 12:42 AM
CSS blocks page rendering because browsers view inline and external CSS as key resources by default, especially with imported stylesheets, header large amounts of inline CSS, and unoptimized media query styles. 1. Extract critical CSS and embed it into HTML; 2. Delay loading non-critical CSS through JavaScript; 3. Use media attributes to optimize loading such as print styles; 4. Compress and merge CSS to reduce requests. It is recommended to use tools to extract key CSS, combine rel="preload" asynchronous loading, and use media delayed loading reasonably to avoid excessive splitting and complex script control.
External vs. Internal CSS: What's the Best Approach?
Jun 20, 2025 am 12:45 AM
ThebestapproachforCSSdependsontheproject'sspecificneeds.Forlargerprojects,externalCSSisbetterduetomaintainabilityandreusability;forsmallerprojectsorsingle-pageapplications,internalCSSmightbemoresuitable.It'scrucialtobalanceprojectsize,performanceneed
Does my CSS must be on lower case?
Jun 19, 2025 am 12:29 AM
No,CSSdoesnothavetobeinlowercase.However,usinglowercaseisrecommendedfor:1)Consistencyandreadability,2)Avoidingerrorsinrelatedtechnologies,3)Potentialperformancebenefits,and4)Improvedcollaborationwithinteams.
CSS Case Sensitivity: Understanding What Matters
Jun 20, 2025 am 12:09 AM
CSSismostlycase-insensitive,butURLsandfontfamilynamesarecase-sensitive.1)Propertiesandvalueslikecolor:red;arenotcase-sensitive.2)URLsmustmatchtheserver'scase,e.g.,/images/Logo.png.3)Fontfamilynameslike'OpenSans'mustbeexact.
What is Autoprefixer and how does it work?
Jul 02, 2025 am 01:15 AM
Autoprefixer is a tool that automatically adds vendor prefixes to CSS attributes based on the target browser scope. 1. It solves the problem of manually maintaining prefixes with errors; 2. Work through the PostCSS plug-in form, parse CSS, analyze attributes that need to be prefixed, and generate code according to configuration; 3. The usage steps include installing plug-ins, setting browserslist, and enabling them in the build process; 4. Notes include not manually adding prefixes, keeping configuration updates, prefixes not all attributes, and it is recommended to use them with the preprocessor.
What are CSS counters?
Jun 19, 2025 am 12:34 AM
CSScounterscanautomaticallynumbersectionsandlists.1)Usecounter-resettoinitialize,counter-incrementtoincrease,andcounter()orcounters()todisplayvalues.2)CombinewithJavaScriptfordynamiccontenttoensureaccurateupdates.
CSS: When Does Case Matter (and When Doesn't)?
Jun 19, 2025 am 12:27 AM
In CSS, selector and attribute names are case-sensitive, while values, named colors, URLs, and custom attributes are case-sensitive. 1. The selector and attribute names are case-insensitive, such as background-color and background-Color are the same. 2. The hexadecimal color in the value is case-sensitive, but the named color is case-sensitive, such as red and Red is invalid. 3. URLs are case sensitive and may cause file loading problems. 4. Custom properties (variables) are case sensitive, and you need to pay attention to the consistency of case when using them.
Case Sensitivity in CSS: Selectors, Properties, and Values Explained
Jun 19, 2025 am 12:38 AM
CSSselectorsandpropertynamesarecase-insensitive,whilevaluescanbecase-sensitivedependingoncontext.1)Selectorslike'div'and'DIV'areequivalent.2)Propertiessuchas'background-color'and'BACKGROUND-COLOR'aretreatedthesame.3)Valueslikecolornamesarecase-insens
