Question
I use Paul Irish's IE Conditional Comments trick to target different versions of IE. In sass how do I apply one of these classes when nested in another class.
.container{
// I need to put a ie8 specific style here which is a .ie8 class applied to the body
}
I'd like to avoid doing this if possible (it's nice to be able to keep the properties together):
.container{}
.ie8{
.container{}
}
Is this possible?
I believe this is what you're looking for - using SASS's parent selector "&", you can do this:
.container {
.ie8 & {
// ie8 specific styles here
}
}
I am a little unclear as to what you are trying to do specifically. But If you are trying to do what I think you are trying to, then you could use a variable.
For example, lets say you only want to have your font color red in IE. You could do something like this.. Although I don't see how using SASS would be all that beneficial in this use case, unless of course you are trying to do something different.
SASS:
You can test this at: http://sassmeister.com/
$ieEightAndNine: "\0/";
.container {
color:unquote(red + $ieEightAndNine);
width:100px;
height:100px;
}
CSS:
.container {
color: red\0/;
width: 100px;
height: 100px;
}
TEST IN CHROME VS IE:
http://jsfiddle.net/3G48v/
I've been tinkering with some css for an HTML markup. The problem I am facing is that there is a style already applied using CSS :first-line pseudo-class. What I want is to change the style of this first line on hover state. Is there a way to apply something like p:first-line:hover ?
You have to define the p:first-line before you can define the chain p:first-line:hover like so:
p:first-line { color: black; }
p:hover:first-line { color: red; }
Fiddle
Very fascinating topic! I tried a jQuery version and found out, that even that won't work. In Firefox, the class has to be applied first to work on hover, as you can see in this Fiddle. But WebKit completely ignores the :first-line on dynamic class adding.
<p class="hovered">Text .... </p>
For Firefox the class has to be set in the HTML code. Now, the following does the job.
jQuery('p').removeClass('hovered');
jQuery('p').hover(function() {
jQuery(this).addClass('hovered');
}, function() {
jQuery(this).removeClass('hovered');
});
But won't work in WebKit.
Yep, you can chain them (have a look here).
p:hover:first-line
let's assume we have this rule:
.ruleA{
color: black;
}
how we set another rule that reads
.ruleB{
color: get the color value of ruleA;
}
is that possible without using jquery, i mean using css rules directly?
No you can't. You can use color:inherit property if that 'div' is nested.
It is not possible with pure CSS. Look into Less or SASS for that kind of functionality.
I have several divs with a determined css class.
I want to manually add pixels to top property:
.class { top: 100px; }
div class="class" style="top:+=50px"
Is it possible do to something like that?
Not with straight CSS. Using a preprocessor like LESS or SASS can do that server-side.
You can accomplish the same thing with jQuery/JavaScript.
var class = $('.class');
var top = class.css('top').substr(0,class.css('top').length - 2);
top += //your value here
class.css('top',top + 'px');
No, not reliably anyway.
There is a CSS3 property called calc() which would do it but it isn't going to work anywhere but the latest browsers and support may be flakey.
More on it here.
http://robertnyman.com/css3/calc/calc.html
Depending on the reasons you want to do this you might want to look into using a CSS Pre-Processor such as LESS or SASS.
What is the reason you want to do this? There may be a solution that isn't immediately obvious from the question posed.
CSS3 transforms might be useful here. Like:
.class { top: 100px; }
div class="class" style="transform:translate(0,50px)"
You'd have to add all the vendor prefixes, though, like:
style="transform:translate(0,50px);-webkit-transform:translate(0,50px);-o-transform:translate(0,50px);-ms-transform:translate(0,50px);-moz-transform:translate(0,50px)"
No, not with just CSS.
You could do it with some server-side code or with JavaScript in the browser.
Another approach could be to use something like LESS or SAAS which support variables and simple calculations.
It's now possible with CSS variables and calc() function.
.class {
--top-add: 0px; /* Default value overridden in inline styles */
top: calc(100px + var(--top-add));
}
<div class="class" style="--top-add: 50px">...</div>
Is there any way to use conditional statements in CSS?
I'd say the closest thing to "IF" in CSS are media queries, such as those you can use for responsive design. With media queries, you're saying things like, "If the screen is between 440px and 660px wide, do this". Read more about media queries here: http://www.w3schools.com/cssref/css3_pr_mediaquery.asp, and here's an example of how they look:
#media screen and (max-width: 300px) {
body {
background-color: lightblue;
}
}
That's pretty much the extent of "IF" within CSS, except to move over to SASS/SCSS (as mentioned above).
I think your best bet is to change your classes / IDs within the scripting language, and then treat each of the class/ID options in your CSS. For instance, in PHP, it might be something like:
<?php
if( A > B ){
echo '<div class="option-a">';
}
else{
echo '<div class="option-b">';
}
?>
Then your CSS can be like
.option-a {
background-color:red;
}
.option-b {
background-color:blue;
}
No. But can you give an example what you have in mind? What condition do you want to check?
Maybe Sass or Compass are interesting for you.
Quote from Sass:
Sass makes CSS fun again. Sass is CSS, plus nested rules, variables, mixins, and more, all in a concise, readable syntax.
CSS itself doesn't have conditional statements, but here's a hack involving custom properties (a.k.a. "css variables").
In this trivial example, you want to apply a padding based on a certain condition—like an "if" statement.
:root { --is-big: 0; }
.is-big { --is-big: 1; }
.block {
padding: calc(
4rem * var(--is-big) +
1rem * (1 - var(--is-big))
);
}
So any .block that's an .is-big or that's a descendant of one will have a padding of 4rem, while all other blocks will only have 1rem. Now I call this a "trivial" example because it can be done without the hack.
.block {
padding: 1rem;
}
.is-big .block,
.block.is-big {
padding: 4rem;
}
But I will leave its applications to your imagination.
The #supports rule (92% browser support July 2017) rule can be used for conditional logic on css properties:
#supports (display: -webkit-box) {
.for_older_webkit_browser { display: -webkit-box }
}
#supports not (display: -webkit-box) {
.newer_browsers { display: flex }
}
The only conditions available in CSS are selectors and #media. Some browsers support some of the CSS 3 selectors and media queries.
You can modify an element with JavaScript to change if it matches a selector or not (e.g. by adding a new class).
I would argue that you can use if statements in CSS. Although they aren't worded as such. In the example below, I've said that if the check-box is checked I want the background changed to white. If you want to see a working example check out www.armstrongdes.com. I built this for a client. Re size your window so that the mobile navigation takes over and click the nav button. All CSS. I think it's safe to say this concept could be used for many things.
#sidebartoggler:checked + .page-wrap .hamb {
background: #fff;
}
// example set as if statement sudo code.
if (sidebaretoggler is checked == true) {
set the background color of .hamb to white;
}
CSS has become a very powerful tool over the years and it has hacks for a lot of things javaScript can do
There is a hack in CSS for using conditional statements/logic.
It involves using the symbol '~'
Let me further illustrate with an example.
Let's say you want a background to slide into the page when a button is clicked. All you need to do is use a radio checkbox.
Style the label for the radio underneath the button so that when the button is pressed the checkbox is also pressed.
Then you use the code below
.checkbox:checked ~ .background{
opacity:1
width: 100%
}
This code simply states IF the checkbox is CHECKED then open up the background ELSE leave it as it is.
css files do not support conditional statements.
If you want something to look one of two ways, depending on some condition, give it a suitable class using your server side scripting language or javascript. eg
<div class="oh-yes"></div>
<div class="hell-no"></div>
There is no native IF/ELSE for CSS available. CSS preprocessors like SASS (and Compass) can help, but if you’re looking for more feature-specific if/else conditions you should give Modernizr a try. It does feature-detection and then adds classes to the HTML element to indicate which CSS3 & HTML5 features the browser supports and doesn’t support. You can then write very if/else-like CSS right in your CSS without any preprocessing, like this:
.geolocation #someElem {
/* only apply this if the browser supports Geolocation */
}
.no-geolocation #someElem {
/* only apply this if the browser DOES NOT support Geolocation */
}
Keep in mind that you should always progressively enhance, so rather than the above example (which illustrates the point better), you should write something more like this:
#someElem {
/* default styles, suitable for both Geolocation support and lack thereof */
}
.geolocation #someElem {
/* only properties as needed to overwrite the default styling */
}
Note that Modernizr does rely on JavaScript, so if JS is disabled you wouldn’t get anything. Hence the progressive enhancement approach of #someElem first, as a no-js foundation.
Changing your css file to a scss file would allow you to do the trick. An example in Angular would be to use an ngClass and your scss would look like:
.sidebar {
height: 100%;
width: 60px;
&.is-open {
width: 150px
}
}
While this feels like a bit of a hack, and may not work perfectly in all browsers, a method I have used recently combines the fact that CSS (at least in Chrome) seems to ignore invalid values set on properties, and we can set custom properties that fall back to their default value when invalid.
(Note: I haven't deeply tested this, so treat it as a hacky proof of concept/possible idea)
The following is written in SCSS, but it should work just as well in standard CSS:
.hero-image {
// CSS ignores invalid property values
// When this var is set to an image URL, the browser will ignore it
// When this var isn't set, then we will use the default fallback for the var, which is 'none'
display: var(--loading-page-background-image, none);
// This part isn't directly relevant to my 'if' example, but shows how I was actually using this custom property normally
background-image: var(--loading-page-background-image, none);
}
I'm setting the custom property from JavaScript / React, but it would likely work regardless of how you set it:
// 'true' case
const chosenLoaderUrl = "https://www.example.com/loader.png";
// 'false' case
//const chosenLoaderUrl = "";
// containerRef is just a reference to the div object, you could get this with
// jquery or however you need. Since I'm in React, I used useRef() and attached
// that to my div
containerRef.current.style.setProperty(
"--loading-page-background-image",
`url(${chosenLoaderUrl})`
);
When chosenLoaderUrl is set to my url, that url is an invalid value for the display property, so it seems to get ignored.
When chosenLoaderUrl is set to an empty value, it falls back to the default value in my var() statement, so sets display to none
I'm not sure how 'generalisable' this concept it, but figured I would add it to the other suggestions here in case it is useful to anyone.
Your stylesheet should be thought of as a static table of available variables that your html document can call on based on what you need to display. The logic should be in your javascript and html, use javascript to dynamically apply attributes based on conditions if you really need to. Stylesheets are not the place for logic.
You can use combination of jquery and css classes i.e. I want to change a font color of certain element depending on the color of the background:
CSS:
.h3DarkMode{
color: lightgray;
}
.h3LightMode{
color: gray;
}
HTML:
<h3 class="myText">My Text Here...</h3>
JQuery:
var toggleMode = localStorage.getItem("toggleMode");
if (toggleMode == "dark"){
$(".myText").removeClass("h3LightMode").addClass("h3DarkMode");
}else{
$(".myText").removeClass("h3DarkMode").addClass("h3LightMode");
}
No you can't do if in CSS, but you can choose which style sheet you will use
Here is an example :
<!--[if IE 6]>
Special instructions for IE 6 here
<![endif]-->
will use only for IE 6 here is the website where it is from http://www.quirksmode.org/css/condcom.html , only IE has conditional comments. Other browser do not, although there are some properties you can use for Firefox starting with -moz or for safari starting with -webkit. You can use javascript to detect which browser you're using and use javascript if for whatever actions you want to perform but that is a bad idea, since it can be disabled.