Nothing in CSS - 0 vs 0px, no, none, hidden, initial and unset

fake italics. Is that what that is? It's just yeah. It's one of those, like,

But

is invalid. I didn't even know that you could So if that's the case, then you just say

HSLA,

to different people authoring essentially the same CSS in different ways, Right? What about role of none? For our like an is like an ARIA role. This is hey. This has no purpose It's really interesting.

you cannot pass a 0.

Yep. The that cannot be unitless

Units, 0, null, false, undefined, and nothing in TypeScript. You've got

past the amount of degrees that your any unordered list that spacing based on how you write it in HTML, if they're each on their own line or if they're not. I hate that. Yeah. Yeah. I hate that kind of funky.

in the syntax website to make sure that we always use units

Degrees is one of them. So font style

nature of not having units on everything Yeah. Is highly confusing to many people and probably confusing to people just learning this stuff, especially because one thing that it leads to is it leads

I should just change this to 10 pixels. You know, it's kind of stated what we are using here. Mhmm.

I do agree that the ambiguous

Oh, that's great. Much of calc breaks with unitless zeros. We talked about that.

values were a mistake. I thought it was kinda interesting. I agree with that statement have

Big maybe. Okay. How about this? We'll put in a style and rule in, but I must not have because there's no way I would have shipped that. You probably pass a Boolean Nothing.

oblique

beyond time, Makes me wonder with the typing of CSS variables, So we have things like pointer events none, which pointer events is is how you control the mouse usage of something. So,

degrees. Did you say degrees?

To save us from ourselves. I wonder if that is actual rule. Can you tell me any other CSS properties that do not take a unit less 0 that do not take a u are they listed in the show notes here? Because Yeah. Are you did you read them? I've well, when you start asking the question, I averted my eyes from the next part of the list. So I'm, like, intentionally, like, trying to look away from it right now. Okay. So you said seconds in milliseconds.

This is something that I ran into it. It would pop up where people say, I don't know where this space is coming from. I put padding 0 on it. I put margin 0 on it. There's no grid gap on it. You know, you do all the things to take away the spacing,

font was oblique.

and I just put 0 and it wasn't working. And I thought, that's weird. Like, what's going on with this? And it turns out that transition delays. 0 is not valid, but

then just put 0. But it may that's a really good point in that, like, if somebody if you put 0 on something and then someone comes around and says, alright. Well, I need to actually you change this to an actual value.

Tab Atkins, who's one of the CSS spec authors. He said that unitless none. Where does the none keyword fall? You don't really think about CSS is having types, but it does right? Like it has percentage, it has turn types, it has Then we have also, really important thing is visibility hidden is not hidden from screen readers. So if you want to take something out of the page but not actually take it out of the DOM, Alright. Let's start with the first one we have here, which is hiding things. If you want to visually

And I ran into this as transition delay.

Good. I like it. Maybe I'll start trying that.

in the past. I said, you know, when there's something in CSS like 0 pixels, your rem, 0% and you just write 0,

But if you put it as 0 degrees or 0 turns or 0 pixels, old properties before we had font face or something to get slanted text or what. Oblique type is a form of type that slants slightly to the right and is used for the same purpose as italic type. Unlike italic type, however, It does not use different glyph shapes. Yes, exactly. So if you have a font that does not have an italic weight, usually with honeypot inputs. So for anyone who doesn't know, a honeypot input is hide from screen readers, but

as a whole. Like, I I'm the type of person. I'm gonna use a unit list value sometimes just for funsies or just because of habit.

shouldn't be sometimes it shouldn't be selectable. I guess it depends on where your cursor starts, But, then obviously it was a

next to an image in HTML, which is kind of weird that

I like to call these ghost spaces, and every now and then, especially when I was teaching the boot camp, I show them some pictures of something, and they want to pinch and zoom into it, but you can't seconds types, has milliseconds types, it has,

Won't allow you to select the text. Right? These are things that are gonna be hiding your own way. Exactly. It's funny. I also learned it, recently because I guess, keyword types, hidden, none, things like that. Do you want to know what all of the official types are for the property? Yeah. Yeah.

because in some cases you want to use your own context menu or You don't want to be able to pop things up. You don't want someone to be able to select something like a good example with user select none would be if you are building a drag and drop of the attribute I had put a 0 on it, so I had I had a bunch of things that were animating

invisible to your pointer events, to touches, to clicks, to gamepad movements,

You just go into the dom and delete that sometimes.

The text inside of the drag and drop interface version. If some if you have 2 elements that touch

as well as the ability for the user to just like highlight text because sometimes all of the stuff related to perspective,

selected everything but the anchor tag. Beautiful.

everything except for the thing. Oh, that's actually really nice. So if you had like a little like an icon font in the middle of 0 will break and anything with timing. So transitions

if you had a paragraph with a span in the middle of it. If you put user select none on the span, 0

select the text that is on it. Yeah. That is an interesting case because it does feel like that would hinder

through something you don't want if somebody, like, long presses on it or holds it for a while or they're like you The browser will just tilt them a bit and you can I didn't even know this? You can specify

not on each on their own line, but if you have an image like a a spammer because there's no way any actual user would be able to get to that input and autofill it. But, like, I often think about that. I'm like, well, then, like, Are the bots really that bad that they can't figure out if

pointer events. None mean that this thing will not accept click events.

So you get this tiny little space And if you do that, to this element is you can either oh, sorry. You can put them on the same line together if you want. That will get rid of it. Or you can set a font size they will now inherit any properties that

Literally, it's easy to conditionally render something. Yeah. So that's that's visibly hiding things. But what about, like, hiding things from interactivity? I know, man. What a world, right?

The click will touch on the image or the div that's over top. So putting a pointer events none on that will just it makes it sort of between 2 in line elements that you can't get rid of.

It's true. These things can really be abused, especially user select none.

On the same line in HTML, are unset, Almost always, you don't want this. It's very frustrating when websites disable this because I simply just want to I don't know that I would have been able to explain it to you without looking it up because it's not something

I think you should try about it now. Alright. One sec. I'm I'm gonna yeah. I'm gonna also try. The answer is yes. It selects,

User select none

would it just not select the span, but the text around it? Should we try it? There

HTML differs, then they know. Okay, well,

are trying to swipe

decorative

user select pretty much ever, but, it's there. And I I I'm sure, like you said, building your own custom context Yeah. Contextual menus and stuff. Slider is another good ample is if you I Or do you do unitless. In my in my ideal world, Robots have ruined everything. Ruined everything. Totally. I know. And and Captcha suck. They're sincerely are awful.

and it will go right directly through that. And Yeah. I use that one quite a bit. Yeah. Just not it's the only thing it's not doing is actually hiding it from the the visible portion of this. Have you ever Yeah. You mentioned, but I I know I've been to a website specifically where I want to highlight some text, and what I do is grab a big old image or something that's, like, sitting in front. Yeah. And a lot of times people are using that, you know, to block paywalls and stuff like that. If you've ever had a, a site that is a subscription based site, they'll put up a little which would then be removed from that ability with that. So I don't know. Yeah. It is one of those things I don't find myself using, the ability for you to interact with something, but not actually hiding it from display. Yeah. Pointer events none is a very handy one. I use it somewhat frequently. If you have some sort of

the classic examples. You have 2 images that are So and

Nothing in CSS. 0. 0 pics. No. None hidden initial unsaid. All the stuff that essentially That's also bad for accessibility. Right? Like, people like to zoom in on stuff. Some people are stubborn, and they're like, I'm not gonna increase my font size. I can read just fine. Let me just zoom in on everything which I I've looked at some people CSS sometimes, and it's like reading a completely different language. Like, what what is the the strategy here? What is the

Oh.

Monday. Monday. Monday.

either undoes or does, context or something like that. And the people who put, like, none for border versus the people who put, like, a 0 for border. Right? Yeah. Which are effectively doing the same thing. You're saying this this border does not exist.

says the absence of something within CSS. My name is Scott Linsky. I'm a developer from Denver. And with me as always is Wes div in front of everything.

So you you had mentioned that the values are different, even different types of values. Right? of a word that was

Oh, yeah. Exactly. I think Like, which of these none types fall into the categories of

Are you going to it depends. Is it gonna take 6 minutes to read them off? Or Length number, percentage, length, percentage, color, image, URL, integer, angle, time resolution transformless transform function custom indent, and that's it.

on this

the type of a property. Correct. I just wanted to make sure that we were on the same page here because pickers and things like that, like okay LCH, which is one that we used. You can use the value of none to indicate

Open wide dev fans, get ready to stuff your face with JavaScript, CSS, node modules, barbecue tips, get workflow, breakdancing,

Like the number percentage. Obviously, 0% is a percentage.

key.

new syntax within CSS that's coming? Didn't, we had,

I went fast just for you. You can slow it down. You wanna get all of them.

being.

nothing.

the fact that making a div or a span into a button or a tab group or anything like that, Then you would say, Okay, I know that this is just a regular old div and this is just ignored by screen readers.

0 is a number. But, like,

0 values, how these play into the types of CSS. Because it's not something that we've ever really had to think about, but it's gonna be something that Yeah. Us as CSS developers are gonna have to think about somewhat pretty soon here. Right? the normal use case of like, oh, I want to select and copy and paste this text, This gives you a lot of options with CSS types. Now I I don't know how closely this is related, but the fact that these things are are different

Boss, and Scott Unset would be 0 seconds, 0 s or 0 MS is valid. So in that case, you do have to pass a unit value. And I posted on Twitter and a couple of people posted

hide something from the page, there's a couple of things you need to think about.

Monday.

soft skill, web development, the hastiest, the craziest, the tastiest this web development treats coming in hot. Here is Wes, Barracuda,

Bosch. Yeah.

any unknown. Never. Right? Like, there's all these things that describe this whole world of typescript

And then I was thinking, like, wow, we actually have quite a bit of that in CSS, as well as a couple of things in HTML we're gonna hit upon as well.

The first one we have is display none. That's going to totally hide the element from the page, We did a whole show on nothing in JavaScript is inside of a blog post, but is not inside of a block quote or something like that, then apply the following styles. And I think it's pretty easy to do that type of stuff. I usually don't.

And have you heard of the at property, And, I was very proud of myself because after I submitted that, I was like,

Dietrich. We're gonna be talking about absolutely

Like, there's a couple properties. What is that? I think you're lying there. For a joke there. So I thought Oh, no. That literally. That's the thing is that like I'm trying to remove this Promise. Yeah. Where you can register Is there a difference between? 0 p x nothing unset initial in CSS.

Just makes it nice and obvious that there's Yeah. Nothing there. Yeah. It's it's kind of the difference between, like, null and undefined,

Or if you do okay c okay LCH 100%. None none. It gives you white. Right? There is no hue. There there is no chroma in this thing.

a o l inside of a u l or a u l inside of an o. You know, they get to do all the the combinations a You're rebuilding it back in in

the same way forever, but, like, I've never thought about it ever even though I'll see it in somebody else's code and just be like, alright. That's how they're doing it. Okay. Fine. But it it doesn't have, like, a huge impact to me. Right?

I would probably keep the pixels there just for consistency's sake. Yeah. But I'm pretty much always do

everything. So if you do okay LCH none none none, it's gonna give you black.

You say I think I probably know the answer to this, but do you say border 0 or border 0 p x? add a number to 0.

And then visibility hidden will still be read aloud to screen readers. So if you do want to hide it from screen readers, you can use aria hidden equals true.

and or occasionally not even lightness. So I I thought that was a really interesting way you approach color because I don't necessarily think about that. That's the same thing as 0. Yeah. Because what you're saying is is is literally that not that the lightness value is set to 0. You're saying, hey. There is no lightness whatsoever.

have 1 element with margin bottom 15 and another element underneath it with margin top 10,

0.

margin and padding off of the unordered list right away.

all of the list styles off Because that's the base style, right? I'll just take them off as I need them, like in the

that. I don't know if that belongs in the show, but I threw it in there. What the heck? It's the absence of I mean, it's like a negative. Yeah. Well, it's like let let me, or no. I guess it is more of a 0 because one of them is just straight up not counting. Your pricing margins are like a very frustrating thing for me in general in CSS. But all right, let's talk about

will be the margin between the 2. So if you around the page. And I think I put like on one of them, I put 2 second delay on it. Another one, I put a 5 second delay. And then on the 3rd one. I put a 0 second delay, so it starts right away, You can't tell that there's indentations, right? Because the padding is based off the parent padding. So if that's the case, you say, okay, when there is a u l inside of a u l or I Ran into something a couple months ago, which was

I rebuilt the syntax color palette are fascinating because you did a Twitter poll. And let me just say,

Because you will course the like you set something and then on a child, I need to take this off.

the values of none and 0 often used. You know? It's it's funny. There's, like, 2 types of developers, especially, like, people who are Are working, like, in a border all the time.

where I put it on each unordered list. Or if it's the case of like a blog post, You're not putting classes on your blog post URLs.

The I guess the only time I, you know, the only time I do think about it is if I'm To go back to the same conversation we had said about using, like, none for border or anything like that is if I'm, like, animating. Right? Let's say I have a situation where I want to animate the border and have that border increase in size from 0 to 10 or something like that to have it do like a little,

But none really makes more sense if there's no border. Right? Especially because you just wanna say, hey. It there's not a border here. Maybe there's a border and you're overriding it, removing it. You're saying no. There's no border anymore.

Yeah, we'll have a nested unordered list.

no. That's just the way it reads. Display. Yeah.

CSS calc in the past.

then I will use UL's inside of the body.

I just have done it I don't know. Do you ever get I've never used that before. I I've never used it before. I think I mostly guessed out of logic and got got lucky somehow. Yeah. Well, ex explain to us what onset and initial values do. Okay. So unset will revert to the inherited value,

And then I'll have that nested.

it might not know what 0 is. But if you have 0 px, you say, all right, We're working with pixels here, You are putting an element on top of it and you are messing up both JavaScript click handlers We can simply just not render the element when it doesn't need to be there because we have frameworks like React and Svelte and whatnot that will If you are trying to to any ARIA role. So if for whatever reason you are using Do Do I change that to something or not? Yeah.

is a value of nothing.

List style is another way that we often use none. List style, none. We don't want to have a list style, which It's one of those things that

the greater value of the 2

There's also

you're not going to have 25 pixels of margin. You're going to have 15. They'll collapse into

make

control issues around that? Like, where you're like, oh, I want list style none for everything. But wait. No. I don't. I actually want list style none for most things in the interface, but I do want the list style for Yeah.

There's certain conditions where it makes sense to have 0 instead of just 0 you don't want someone to be able to try to drag something and then accidentally pinch and zoom on the photos themselves rather than the entire app because that also is annoying if somebody Next one we have here is inline elements.

Carte blanche take When you try to remember back in the day, people would stop. You would disable the context menu and then all of a sudden they They have to scroll side to side. You know, you get that bit of a pain in the butt. So that's how you disable that. Just about never do that, though.

and they both have margin,

I do feel like I might use So unset basically says, a button is hidden or an input is hidden? You know? In in my experience, the honeypot inputs don't do very much. I've I've added, well, like, I have a form to get this against I'll just throw a honeypot field on this thing and solve it. Okay. Never mind. They figured it out in, like, no time. So Yeah, I think we need a

that none somewhat frequently as well just because that's like a situation. I'll find myself refactoring some code. You know what is worse when you can't remember if it's none or 0? What?

Collapsing margins in CSS is kind of an interesting one. I don't know. Would you consider this a none No, Hopefully, you learned a thing or two. Anything else to add there, Scott? No. I was trying to, like, think

There's only lightness or darkness

you know, right? Yeah, explicitly nothing there is explicitly nothing, whereas 0

if you put if you have an unordered list in your footer or in your header and your nav, something like that. Yeah. I feel like that's the one lesson I never learned. I like start a project. I go to say, oh, I don't want these list styles everywhere. I got turn them off, and I start building, and I'm like, oh, no. Wait. That's a dumb idea. And I feel like I do that every project. You know, the one that I do is I'll take the

just 0. I don't know. Actually, I would love to find some of my code for that. You know, I've been a unit less 0er for my whole life. However, I ran into a couple of issues with I'll ask you about border. So you're taking a border off.

Yeah. You know, it is one of those things that I feel like So let's get Before Sorry. Go ahead. We even do that, Les, I wanted to bring something to your attention that you might not know about.

and that can be handy if your inputs

false or disabled. True. As in this thing is disabled, but then also be able to toggle it. That's pretty much the only time I'm using disabled false.

is if you are

because they've disabled that.

thing and like 18 versions of Babbel when I'm searching, so beside each other. And that's just I call it ghost space.

bundled node module

Oh, man. Is that okay? I don't do that. I guess I thought I did that, there the state is not disabled, as in this thing is active, their mouse is in the wrong spot. You know, sometimes you can accidentally select the image and try to instead of actually trying to make a swipe. So there's little edge cases. I wonder if you have like a carousel with, like, a icon font or something. You had a font or or a font specifically that might have a triangle symbol, and you want that to act more like a button. You don't want it to be selective, all those types of things. You know, 1 I'm wondering is

not a zilch 0

will make it true So you can set. I always do disabled equals hell yeah, brother, because it doesn't matter what you pass to the disabled. Same with autoplay.

Show it or hide it. Yeah. You're right.

A lot of times people use this when they're developing an app and then they implement their own your thingy, you didn't want them Like the actual icon itself. You put user select none on your icons. Yeah. I just tried it on an anchor tag, and it and then you have 2 like that will visibility. That's kind of the same thing as visibility hidden.

on something to an input, and I wanna have it occasionally be disabled if the different

will,

Zoom into That. If you put opacity 0,

input or something that you would have. You would you would probably want screen readers to ignore that. Right? Yes. But I think yeah. That's a good point because you could like,

the browser and screen readers. Okay. This is something that's clickable and should be focusable. I was gonna say is that like you think like a like a honeypot you use every single day. That's what a lot of people said. Oh, rather than you going and trying to overwrite And it's usually always valid things. It's just some of these learned from somebody else, and therefore, they've picked up different habits. Right? That's interesting because like I would say probably most people listening to this podcast would say like or even have us go as far as have a lynching rule that say, all right, if you're saying 0 output into a pixel value rather than not Adam. Who was it that came on and and talked to us about it? Almost everybody got it wrong. I think it was something Yeah. Which is why I was, like, second guessing myself immediately.

Beautiful. Alright. Thanks for tuning in. Catch you later. Peace.

The simple existence to 0 on the parent and then reset the font size on the actual element in that by setting a font size to 0, Then we have visibility hidden. That will visually and this is this happens with like Facebook and whatnot, as well as from screen readers.

a tab or something that you're like, You know what, I'm using this not in the way that it is meant to be or I do not want screen readers to be able to pick up on it.

an input or

What is so we also have disabled false, which The only time I use disabled false, which is essentially to say, like,

zooms your entire website

from the user, doesn't matter. It's the existence of them. So that's why if you're trying to toggle them in most reactants felt they'll take care of that with the actual Boolean.

for a full archive of all of our shows.

Is if I just am using a straight up JavaScript Boolean toggle I got both of those correct. I can prove it.

Peace.

For whatever reason, a robot that is trying to spam you

will try to

an input that you put on a form

You can put in to Svelte, And it takes care of adding and removing it. But if you pass a string of true or false, interesting. Very interesting. Wonder how far you can go. I guess you could just use skew.

But if I put you say role equals button, and it will show the that you usually visually hide It must be 0% for the hue, which is another one that I would have thought. Wow, interesting.

But anyways, role of none will indicate that the element should not be mapped Raycast and whatever searches. And if I'm searching for a line of code, And that's because Google Photos.

a photo. This happens a lot to my kids like on

And don't forget to subscribe in your podcast player or drop a review if you like this show.

submitting forms safely on the Internet because Autoplay equals. Yeah, buddy. It doesn't matter because the value of those attributes be used for I don't know. I never use role of done. Do you do you use this? That's a good question. I don't I don't know that I I have used it in the past. I wish that I just had a search on my entire computer That I could search all the code I've written because I use all these like in HTML. So user scalable equals no.

we should do another show on Aria role equal. The opposite of role is often,

And then Aria hidden true. We talked about that. We don't have to go over that one again. So that is Well, disabled false is true.

Head on over to syntax.fm

0. I I add 0 to that, a pixel or a, unitless

it's not going to work. HTML doesn't work that way. You are dead on. Yes.

unitless answer. 0.

an element that takes up 40 pixels high and 30 pixels wide and you have visibility hidden on that, then the space that it takes up Will not go away.

hide the item, but it will not give up its space in the document flow. So If you have to stop people from like viewing source like that was the trick that people did. I'm pretty sure you can still do that

all of the styles to match what your website is. You can go in and select all of those elements that have their styles and you can say unset. And what that will do is it will say, Okay,

and therefore

unset it, inherit.

something that has, like, let's say you have 6 cards interface.

Yeah, and I don't know if you ask me what are the differences between unset and initial? that would be kind of cool to be able to search my actual code. I guess I could use GitHub search.

Interesting. Last ones we have here are some HTML bonus ones. So these are no none. All true

and it will say, Okay, well, somebody set a variable on me. I'm going to ignore that.

I'm going to go up, look up the DOM tree to whoever has now set a CSS variable and grab that value.

hey.

whatever this thing,

This will stop your user from being able to pinch and zoom on a website.

and there's a CSS variable on all 6 cards. They've been applied 0 seconds and 0 are not the same thing in CSS. And I thought, and say disabled false. I guess I don't use this then. Yeah. So the simple with all HTML attributes, except for ARIA attributes.

and you see something and you're like, oh, that that doesn't look like the rest of the website. And it's because whatever third party embedding thing they're using

is applying its own CSS because they're going to see it in the DOM. Yeah. So and then on on your server, you can say, all right, well, if they filled in the honeypot, if you are embedding some HTML and CSS from an external widget, and they put their own styles on it. You know, sometimes you go to a website it always just finds some like What are they going to use? Are they using pixels? Are they using the rems? Are you using degrees? Are you using percentages? And all of HTML attributes with you. What are you talking about? Yeah. If you Go go make a go make an input Either I'll make a utility class,

It will allow you to

If you

and you say, Okay, but this 1 card, I don't want it to take that value. I want it to inherit from whatever is a little bit up higher.

the styles applied how much it tilts. You can that man, like, what else is there in CSS that is none, 0, hidden?

and it will ignore

If if you have applied a a p

the the reset that comes from the browser, which is typically just black for text or Yep. Whatever the purple blue colors that we have for links and stuff like that. Default browser styles. Default browser styles. Yeah, and people are saying, like, when would you ever want to use that.

But the red that you assigned to the p directly

will be removed from it. And initials just gonna say

Rather than reset the value to whatever it was. You can unset it Like in my in my case, I always put grunge over top of my text.

that have been set above me. So common ones are colors, all of the font stuff, font family, things like that.

anything set directly on the the element itself where initial will revert back to the browser default itself.

other means of the color being defined. Like, let's say you have a div wrapper around that paragraph tag with a color. That color will still apply to the p tag,

color. If you you say p color red, some of these new color,

Another kinda interesting use case that I had. Sorry. Before to interrupt you, that's a such an awesome use case for stuff that I have in the past taken a look at that and just been like, I guess I'm just gonna copy and paste some CSS, or I'm gonna abstract and start dropping classes in here if I can. Yeah. But it it that's a great use case for that, and I've never considered that at all. Another use case is with CSS variables.

A couple of use cases for like if it's 1 it works. But if it's 0, you can get into some trouble. So maybe setting it to to p x is a good idea in that case.

and then you use unset in the next one, that p color will get its color from using a CSS How do you personally control that? Yeah. I will usually Welcome to Syntex

and there used to have to be a little bit of a a workaround or make sure that, hey, you're not using display none on something that Could eventually become a problem here, right? Yeah. And code that you want to be visible. That's a good point. And I don't think we do that as much because

You run the risk of robots not being able to see it. That's a really good point. Yeah. Because we used to hide things on the you know, back more in the jQuery days. I remember hiding things all the time, I guess I did not know that. Yeah. Oblique is

transform without doing some JavaScript or something like that. But also to, you know, another thing it. To keep in mind about these is the SEO part of things. If you want something to, quote unquote, be available in the DOM, just like it is for screen readers, display none

And then the last 1 we have here is opacity.

visibility hidden

counting towards your SEO juice if it's display none. So if you're hiding something on initial page load and then loading it in after for some reason using display none,

But What what do people use that for for for fading it in when you do want to show it? Right? Yeah. Because you can't really fade in

will hide it from crawlers as well. I mean, it's not going to be, Okay. Did I actually Did I goof up? Is everybody else right about these? So yeah.

for the record, Wes,

having unitless values is either only there for

Let's talk about unsaid in initial, which

whatnot. We talked about will break it. You pass a unit 0. That makes sense. Right? It's so that would be very ambiguous, but also, yeah, Does feel like a lot of these newer properties

I can prove it that I got both of them correct. I don't think I would have got it. I got both of them correct. Yeah.

longevity sake or to match things that already exist. Right? Mhmm. Where null or none or

transition is a fairly newish property. And I have no idea if that actually comes into play here, but just first thing I thought of.

they are are a couple properties in CSS that will break when you omit the unit and just put 0.

And the way to the way to get around that

the ghost space is determined by the font size, and it will get rid of it. Interesting.

0 units versus 0 itself.