Does the media query operator "not" actually work? - css

I actually want to trigger :hover effect only on PC that have mouse, but not on hybrid ones (mouse + touch).
My query is :
#media not (any-pointer: coarse) {
tag:hover { some effect }
}
What I want to say is : apply hover to PC that have not at least one coarse pointer (touch).
But it doesn't work, neither on chrome nor on firefox or edge.
What I am missing ?

According to MDN
if you use the not or only operators, you must explicitly specify a media type.
This snippet adds screen to the media query in your question.
On a laptop without touch screen it appears to work, that is hovering over the div does change it to cyan. If you change the 'coarse' to 'fine' then the hover does not work because the laptop's mouse is considered a fine pointer.
div {
width: 20vmin;
height: 20vmin;
background: pink;
}
#media not screen and (any-pointer: coarse) {
div:hover {
background: cyan;
}
}
<div></div>

Related

Responsive CSS on Display-Listings-Shortcode

I installed a plug-in called Display-listings-shortcode, and added the columns-extension to allow for columns the blogs halfway down the homepage at RitaNaomi.com will be horizontally displayed on a web browser. It looked whacky at first with titles being scrunched beside and underneath the image, but eventually i figured out how to edit the .display-posts-listing class to change the display
.display-posts-listing .listing-item {padding-bottom:30;}
.listing-item
{
float:left;
width:22%;
margin: 40px
}
But when I look at it on a mobile device, they're all scrunched together as if it was still being displayed on a laptop. I want to have it listed vertically and not horizontally, because thats the way it would fit best.
I tried (and it didn't work) to use #media to change it through the css, but it didn't work.
#media handheld {
.display-posts-listing .listing-item {
clear: both;
display: block;
}
.display-posts-listing img {
float: left;
margin: 0 10px 10px 0;
}
}
You shouldn't be using #media handheld {} since it's been deprecated according to MDN.
You're better off targeting pixel-width values. You may need a couple queries, and some of the oldschool standards were 1023px, 767px. Feel free to replace the 900px below with whatever works for you.
#media only screen and ( max-width: 900px ){
.display-posts-listing .listing-item {
/* CSS Here */
}
}
Removed the custom CSS that was already added from the original theme. It was interfering with the Columns display.
Not using #media handheld {} because it was deprecated (thanks to xhynk for the response), and instead used the command (max-width: 768) , the point at which the title and image css look funky.
To make the title display on its own line on a bigger screen, i added this to my CSS:
.display-posts-listing .listing-item .title { display: block; }
And now i'm using the above media query to figure out how to style it on smaller devices.
Complete CSS: https://gist.github.com/billerickson/17149d6e77b139c868640a0ed3c73b3a

Bootstrap layout media queries not working at 767px on Chrome

I have a Chrome-only problem with my Bootstrap (v3.3.5) layout css at exactly 767px where the layout styles simply aren't being applied.
Here's the behaviour after experimenting with the console on 3 browsers...
Chrome
-window.innerWidth of <= 766 - correctly shows mobile layout
-window.innerWidth of == 767 - incorrectly applies no layout styles
-window.innerWidth of >= 768 - correctly shows full screen layout
Firefox
-window.innerWidth of <=766 and ==767 - correctly shows mobile layout
-window.innerWidth of >=768 - correctly shows full screen layout
Safari
-behaves fine although window.innerWidth doesn't correctly correspond to the breakpoints (perhaps something to do with Safari not accounting for scrollbars in the same way)
All my media queries have been created as follows...
#media (max-width: 767px) {
/*small view*/
}
#media (min-width: 768px) {
/*full view*/
}
I've experimented changing these values so there's an overlap (e.g. a min-width of 767px) but it has no effect.
Apologies if this is a little vague, but I don't really know where to go from here in investigating the problem and have found only one report of similar behaviour from a previous version of bootstrap (https://github.com/twbs/bootstrap/issues/1531).
Does anyone know of any possible reason that I'd be seeing this on Chrome only? Either way, any advice on an appropriate way to investigate would be very much appreciated.
-- EDIT --
After hours of research I tested this simple file...
<html>
<head>
<style>
#media (max-width: 767px) {
.headlineText {
font-size: 10px;
color: red;
}
}
#media (min-width: 768px) {
.headlineText {
font-size: 10px;
color: green;
}
}
</style>
</head>
<body>
<h1 class="headlineText">this is a headline</h1>
</body>
</html>
On Chrome only - at 767px the text is neither green or red - it's black, Times New Roman, and considerably bigger than 10px. Of course I can't replicate this by uploading to a fiddle/codepen - so it must be something to do with the fact I'm running on a localhost (via MAMP). Absolutely zero ideas why that would be the case, but at least it doesn't seem to be something that will affect me in a live environment
Chrome (for me version 89.0.4389.82 on Win10) seems to work with fraction of pixels. Hence, increasing all lower breakpoint thresholds by .9px solved the issue for me. So for example
max-width :767px needs to become max-width :767.9px
Make this full screen and resize your window. It works for me in Chrome and has no display of "does not work" in between.
.works {
display: none;
}
.does-not-work {
display: block;
}
#media(max-width:767px){
.works {
display: block;
}
.works::before {
content: 'max-width: 767px | ';
}
.does-not-work {
display: none;
}
}
#media(min-width:768px){
.works {
display: block;
}
.works::before {
content: 'min-width: 768px | ';
}
.does-not-work {
display: none;
}
}
<span class="works">works</span>
<span class="does-not-work">does not work</span>
Side note, based on comments: About a year ago I had the same issue with a huge website. Result of a team of 6's work of nearly two years. Bits of code pouring in from all sides. I was the one gluing front-end together, making sure it all worked. You can imagine #media queries were a mess. I only got rid of the bug by refactoring all queries using mobile first principle - I grouped all #media's using Bootstrap's exact order. Fixed it for me. To this day I don't know what caused it. It was (slightly) broken on (exactly) 768px and 992px before.

How to hack unsupported mix-blend-mode CSS property?

I'm programming gallery of images, with specific hover effect. When user comes over the image, I use ::before pseudoelement to create "curtain" over the div with image using mix-blend-mode CSS property:
div.img::after {
content: "";
display: block;
width: 100%;
height: 100%;
position: absolute;
top: 0;
left: 0;
z-index: 2;
mix-blend-mode: soft-light;
background-color: red;
}
Resulting effect is like this:
But unluckily, IE (and some others according to caniuse) does not support this property and displays full red rectangle over the image and therefore it is not visible.
Is it possible to hack this mix-blend-mode behaviour to act like in Firefox or Chrome?
If not, is it possible to hide covering div or set it semi-transparent if and only-if mix-blend-mode is not supported?
Thank you
I know this is an old question, but you can also use the #supports feature query to detect if a certain property is or isn't available.
#supports not (mix-blend-mode: multiply) {
.image {
...
}
}
If you're interested, you can read more about the feature query at: https://developer.mozilla.org/en-US/docs/Web/CSS/#supports
If you don't want to use plain opacity as a fallback:
Approaches to cross-browser support
Javascript polyfill
This will be slow, and will not allow you to easily animate. However, it will let you create an alternate image for each of your matching images, and you can then fade the opacity or do other CSS transition tricks between the two.
http://codepen.io/brav0/pen/bJDxt (not my pen - uses multiply, not soft light)
Server side processing
Wouldn't be my first choice, but if you control the server-side code, you can prepare alternate images using server side imaging libraries (GD, etc)
Only enabling the effect for supporting browsers
Css hacks for detecting IE
#media screen { #media (min-width: 0px) {
div.img::after{ ... }
} }
Using JavaScript
if (window.getComputedStyle(document.body).mixBlendMode !== undefined)
$("div.img").addClass("curtain");
...and the CSS...
img.curtain::after { ... }

Why do I have to put media queries at the bottom of the stylesheet?

I am new to learning responsive design. What I have noticed on my journey is that when I put media queries at the bottom of the stylesheet, everything works flawlessly in regards to breakpoints. If I put the media queries at the top of the stylesheet, nothing works, and only recently I found out that I need to add !important and max-DEVICE-width ( as opposed to max-width) to the css that is being changed.
Why is this? Why do the media queries work on both desktop and mobile when put at the bottom of the stylesheet.
Why is it that when I put media queries on the top of the stylesheet I need to add !important and also max-DEVICE-width in order for the breakpoints to work on desktop and mobile?
Because css is read from top to bottom. The rule that is set last, is the one that will be executed.
Translating, it is like this:
#media (max-width: 600px) { //If my screen fits this size
.text {
color: red; //Paint it red
}
}
.text {
color: yellow; //Now, forget about everything and paint it yellow!
}
When you add !important is like saying:
#media (max-width: 600px) { //If my screen fits this size
.text {
color: red !important; //Paint it red, and don't change it ever!!!
}
}
.text {
color: yellow; //Ok, I'm not going to paint it yellow....
}
CSS is read from top to bottom.
Everything that is below some other css will overwrite what's on top of it.
It is possible however to use !important at the end of a CSS parameter to make it overwrite everything else
body{
background-color: black !important;
}
body{
background-color: pink;
}
The background-color will be black.
If you remove the !important, it will be pink.
Media queries cascade with the rest of the stylesheet. You can intersperse media queries within your stylesheet, and so you can also cascade styles as needed.
For example:
.my-class {
color: red;
}
.my-class--modifier {
color: blue;
}
#media screen and (min-width: 760px) {
.my-class--modifier {
color: green;
}
}
.some-other-class {
width: 200px;
}
#media screen and (min-width: 760px) {
.some-other-class {
width: 700px;
background-color: gray;
}
.some-other-class .my-class {
border: 2px solid red;
border-radius: 4pt;
}
}
This works precisely due to CSS's cascading nature. You can organize media queries as required based on sections, individual selectors and more.
Basically you are using media queries when you want to apply CSS styles depending on a device's general type (such as print vs. screen), specific characteristics (such as the width of the browser viewport, or environment (such as ambient light conditions).
When you started designing, you generally started doing it for one device of known specifications. So you design it according to you current device and then apply it for other screen sizes.
Hence the order goes like this: Make complete design --> Add the media query to fit for desired screen sizes at the bottom.
It is preferrable to write the query at the bottom became of precedence. That will save you from stress of using important! everytime.

How can I avoid media query overlap?

The cascade is what makes CSS special and powerful. But in the case of media queries, overlap can seem problematic.
Consider the following CSS (continuing rules for CSS media query overlap):
/* Standard - for all screens below 20em */
body { color: black; font-size: 1em; }
/* Query A - slightly wider, mobile viewport */
#media (min-width: 20em) and (max-width: 45em) {
body { color: red; } /* supposed to be unique for this width */
}
/* Query B - everything else */
#media (min-width: 45em) {
body { font-size: larger; } /* because viewport is bigger */
}
So when the screen is exactly 45em wide, the overlap at 45em will be treated according to the standard CSS cascade:
All max-width: 45em definitions will be applied first,
and all min-width: 45em will be applied thereafter.
Consider these two conditions:
All text would normally be black, but Query A is unique and has color: red.
Since Query B is for larger viewports, it's text has the CSS font-size: larger.
Therefore, at a width of exactly 45em, we'd get big and red text. What would be the best solution to avoid this?
I see two possibilities:
Re-declare the text to have color: black in Query B, but then you're managing two declarations if you choose to change the color in the future. (Of course, not such a problem with this single line of code, but imagine there's a lot of other declarations and selectors.)
Avoid overlap by using pixel values like max-width: 799px and min-width: 800px, but then you're using pixels — I guess they could be 49.9375em and 50em, respectively. Though what if the default is no longer 16em and something gets rounded? And we're still not certain what happens at that gap. (A black hole that breaks the space-time continuum?)
Both have their drawbacks... any other ideas?
The only reliable way to create two mutually exclusive #media blocks for any given media query is to use not to negate it in one of the blocks. Unfortunately, this means repeating your media query once for each #media block. So, instead of this for example:
#media (max-width: 49.9375em) {
body {
color: red;
}
}
#media (min-width: 50em) {
body {
font-size: larger;
}
}
You would have this:
/*
* Note: Media Queries 4 still requires 'not' to be followed by a
* media type (e.g. 'all' or 'screen') for reasons I cannot comprehend.
*/
#media not all and (min-width: 50em) {
body {
color: red;
}
}
#media (min-width: 50em) {
body {
font-size: larger;
}
}
Interactive jsFiddle demo
This is very effective at closing the gap with range media features like width and height since it essentially turns this into an either-or scenario. But, like your first two options, it isn't perfect: as mentioned, you have to repeat the same media query twice, and add not to one of them. There is no if/else construct for #media as described in Conditional Rules 3.
Although I mention this in my answer to your previous question:
From my experiments it would seem Safari on iOS rounds all fractional pixel values to ensure that either one of max-width: 799px and min-width: 800px will match, even if the viewport is really 799.5px (which apparently matches the former).
It should be noted, still, that I've noticed some quirks when it comes to rounding. That said, I haven't been able to find a fractional value that would evade both media queries and end up not receiving styles from either set of rules (which, by the way, is the worst that can happen, so don't worry about potentially creating a space-time rift). That must mean browsers — at least, Safari as I've tested — do a reasonable job of ensuring they satisfy media queries even if you have values that differ (by exactly 1 CSS pixel).
When it comes to units with larger gaps that can be observed on desktop browsers, though, like ems, there is a much larger margin of error. For example, one comment suggests using 49.99999em instead of something more arbitrary than 49.9375em, but apparently there is a difference, at least with a default font size of 16px.
I simplified your code, changed the media queries to use decimal values, and put the code in jsFiddle:
#media (max-width: 49.9375em) {
body {
color: red;
}
}
#media (min-width: 50em) {
body {
font-size: larger;
}
}
If you resize the Result pane to exactly 800 pixels (the text will update to guide you along), you actually end up with different results depending on whether #media (max-width: 49.9375em) is used, or #media (max-width: 49.99999em) is used (I was surprised by this too)...
Either way, you're right: option 2 has its drawbacks too. I'm not particularly fond of it, to be honest, because I wouldn't want to crack my head over device and user agent quirks which are out of my control. If you're like me, I suppose it would be better to go through the inconvenience of redeclaring your rules at the cost (?) of being more vigilant around your code, as that's at least still within your control as an author.
For me, the best way is to keep a gap of 0.01em:
#media (min-width: 20em) and (max-width: 44.99em) {
body { color: red; } /* supposed to be unique for this width */
}
#media (min-width: 45em) {
body { font-size: larger; } /* because viewport is bigger */
}
I recommend you to read this article for the details and the comparison of the different solutions to prevent media query overlapping.
Cheers,
Thomas.

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