I want the left css property to take the value from the html element using attr like this
<div left-value="30px"/>
div{
left: attr(left-value);
}
is this even possible? it works with after and before.
The attr css function is appearently very powerful but yet very limited as described here:
https://developer.mozilla.org/en-US/docs/Web/CSS/attr
Note: The attr() function can be used with any CSS property, but
support for properties other than content is experimental, and support
for the type-or-unit parameter is sparse.
Anyway there's a trick you can use to get quite the same result but using css custom properties. Instead of defining an attribute on the html element that you are going to read in your css rule using attr, you can just set that same value on a custom property using the inline styling. Then in your rule just use that custom property to set the left properrty of the element.
Here I also put a container with position relative, to better highlight the correct working of this solution:
.container{
position: relative;
border: dashed 4px lightgray;
height: 100vh;
width: 100vw;
}
.container > div{
position: absolute;
left: var(--left-value);
border: solid 1px gray;
background: red;
width: 20px;
height: 20px;
}
<div class="container">
<div style="--left-value: 20px;"></div>
</div>
Of course it doesn't look very smart to use a custom property instead of using directly the left property since you are using the inline styling already. There are cases when this solution could be the way to go.. but here indeed it's not really changing the game
First-of-all there is no such attribute as left-value in HTML. You have to use pre-build attr in HTML cuzz it's not react. Secondly if you want to left align the just simply use position and left attr of css or just do some styling using margin-left.
Related
Is it possible create a custom class for example:
border {
border:1px solid;
}
and apply directly in a tag, without need of class=""?
Example: <div class="row" border></div>
Well, you can. But as #G-Cyrillus said in the comments to create a custom attribute in your HTML element it is better to use HTML data-attribute to stick with the HTML standards. Then you can style your element without adding a class attribute.
So if you don't want to add it as a data-attribute you can style it like this:
[border] {
width: 100px;
height: 100px;
border: 1px solid;
}
<div class="row" border></div>
And with the data-attribute (Which is the standard one) you can do the same:
div[data-border] {
width: 100px;
height: 100px;
border: 1px solid;
}
<div class="row" data-border></div>
What you want can be accomplished by using a javascript framework like VueJs or React.
I know, in VueJs it's called a prop that you pass to a child element. Whether or not the prop (border in your case) is passed down, the styling is applied or not.
I have written a class for a textfield with a certain style. The field appears at 2 very different place within the website, with different parent elements. The second need another margin-top. What is an efficient way to change the original margin-top, since I cannot use pseudo-classes?
js fiddle
HTML
<div class="some_parent">
<div class="my_styled_field"></div>
</div>
.....
<div class="some_other_parent">
<div class="my_styled_field"></div>
</div>
CSS
.my_styled_field{
margin-top: 2rem;
}
.some_other_parent .my_styled_field{
margin-top:3em; //what ever you want
}
this is the way to apply some other styles to the same class, having different parents .
Pretty sure the most efficient way - most of the time - as in best performance, would be to add another class to your second styled_field.
If you add another class to your second styled_field, you would need only 1 reflow to reach it:
.newclass{margin-top:5px;}
Whereas using the descendant selector which others are selecting is surely worse performance, this means the browsers has to check a lot of elements recursively:
.parent .styled_field
If you don't want to add a class for some reason, better performance than the descendant selector would be the child selector:
.parent > .styled_field
When thinking about css performance, remember that even though we read left-to-right, browsers read right-to-left.
Where we would check all .container elements for an image-tag, browsers find all image-tags - then checks if they are in a .container
Using CSS class hierarchy:
.some_other_parent .my_styled_field {
margin-top: 2em;
}
Youc can do this:
FIDDLE EXAMPLE
.some_parent .my_styled_field{
width: 3rem;
height: 3rem;
margin-top: 2rem;
background-color: red;
}
.some_other_parent .my_styled_field{
width: 4rem;
height: 4rem;
margin-top: 4rem;
background-color: green;
}
This way, you aply style to .my_styled_field depending on his parent element.
I'm trying to alter the style of something based on wether or not its parent div is being overflown.
.pDiv { display: block; width: 300px; height: 100px; border: 1px solid rgb(0,0,0); }
.cDiv { display: block; padding 4px; border-bottom: 1px solid rgb(0,0,0);
.pDiv:overflow .cDiv { border-bottom: none; }
<div class="pDiv"><div class="cDiv">child 1</div><div class="cDiv">child 2</div><div class="cDiv">child 3</div><div class="cDiv">child 4</div><div class="cDiv">child 5</div></div>
is it possible to do something like this? I would use the last-child pseudo-selector, but the number of children can vary, so I want it to remove the border-bottom of the last-child ONLY IF the parent div is being overflown. I want a pure CSS solution too please, no JS!
CSS cannot select based on used or computed styles of any kind, so you're out of luck.
It seems a handy solution for this is being cooked up: https://developer.mozilla.org/en-US/docs/Web/CSS/CSS_Container_Queries
According to css-tricks, the feature "#container brings us the ability to style elements based on the size of their parent container."
You should already be able to use it, but beware that not every browser supports this yet.
This way, you might (read the note) be able to get out with something like:
.parent-div {
max-height: 10rem;
overflow-y: auto;
container: size;
}
#container (min-height: 10rem) {
.parent-div:last-child {
border-bottom: none;
}
}
The main idea here being that if the element reached it's maximum height, then it's all but always overflowing — so we just apply the style so long as it's at it's maximum height.
Unfortunately, my own browser does not support this yet, so I can't guarantee you it would work the exact way as it is written above. But if you refer to the 2 pieces of documentation I provided, you should be able to come out on top 🤓
Note:
The css-tricks page also mentions that "Currently, you cannot use height-based container queries, using only the block axis". I'm hoping this simply means using the full size axis is necessary in this case, but I'm not able to test this.
If someone could verify whether this solution works and then leave a comment here, that would be very much appreciated. I'd edit this answer and credit the person.
Question
Can I style just a part of a single character?
Meaning
CSS attributes cannot be assigned to parts of characters. But if you want to style only a certain section of a character, there is no standardized way to do that.
Example
Is it possible to style an "X" which is half-way red and then black?
Not working code
<div class="content">
X
</div>
.content {
position: relative;
font-size: 50px;
color: black;
}
.content:after {
content: 'X';
color: red;
width: 50%;
position: absolute;
overflow: hidden;
}
Demo on jsFiddle
Purpose
My intention is styling the Font Awesome icon-star symbol. If I have an overlay with dynamic width, shouldn't it be possible to create an exact visualization of scores?
While playing around with a demo fiddle, i figured it out myself and wanted to share my solution. It's quite simple.
First things first: The DEMO
To partly style a single character, you need extra markup for your content. Basically, you need to duplicate it:
<div class="content">
<span class="overlay">X</span>
X
</div>
Using pseudo-elements like :after or :before would be nicer, but i didn't found a way to do that.
The overlay needs to be positioned absolutely to the content element:
.content {
display: inline-block;
position: relative;
color: black;
}
.overlay {
width: 50%;
position: absolute;
color: red;
overflow: hidden;
}
Do not forget overflow: hidden; in order to cut off the remaing part of the "X".
You can use any width instead of 50% which makes this approach very flexible. You can even use a custom height, other CSS attributes or a combination of multiple attributes.
Extended DEMO
Great work on your solution. I’ve got a version that uses :after (instead of duplicating the content in the HTML) working in Chrome 19.
http://jsfiddle.net/v5xzJ/4/
Basically:
Set position:relative on .content
Position :after absolutely
Set :after to overflow:hidden
Adjust the width, height, text-indent and line-height of :after to hide bits of it.
I’m not sure if it’ll work well cross-browser though — the em values will probably work out a bit differently. (Obviously it definitely won’t work in IE 7 or below.)
In addition, you end up having to duplicate the content in your CSS file instead of the HTML, which might not be optimal depending on the situation.
I have an HTML django template page that is both RTL and LTR (depends on user's locale).
The CSS of this page is stored in another file, and that file is currently static.
What is the best way to switch the attribute left and right according to the locale? Is there a built in attribute in CSS for this problem? (I don't want to use JS, it feels too messy)
I have:
.elem{
left: 10px;
bottom: 10px;
position: absolute;
}
I want something like this:
.elem{
right-or-left-according-to-html-dir: 10px;
bottom: 10px;
position: absolute;
}
Currently the only option I can think of is turning the file into a template also:
.elem{
{{dir}}: 10px;
bottom: 10px;
position: absolute;
}
Is there a better way that will let me keep my CSS file static?
You say you're making the document rtl or ltr depending on locale. In that case you can use the :lang() selector to make certain parts of your document have styling depending on the locale.
http://www.w3.org/wiki/CSS/Selectors/pseudo-classes/:lang
http://www.w3.org/TR/css3-selectors/#lang-pseudo
If you want a little more support (IE7+) you could use the attribute selector selector[lang='en'] though that will only test the attribute on the specified selector.
http://www.w3.org/TR/css3-selectors/#attribute-selectors
If you specify the language in the html element (which you should, with lang="en" for example) you can just put the html selector in front of the class you want to apply in certain locales:
.elem {
margin: 0 10px 0 0;
color: blue;
}
html[lang='en'] .elem {
margin: 0 0 0 10px;
}
Even better, if you specified the dir attribute you can directly use that in css like so:
.elem[dir='rtl'] {
margin: 0 10px 0 0;
}
Please note that with a class on the body element you will always depend on that class always being there. But the dir and lang attribute can be specified on a more specific scope, like a single div, and still be used in the css along with styles for the 'other' reading directions.
Edit
Lastly, to gaze into the future, the CSS Selectors 'Level 4' will include a psuedo tag which will be able to filter on text directionality. Of course the specs are in development and adoption by browsers may take years before it is possible to reliably use it:
http://dev.w3.org/csswg/selectors4/#dir-pseudo
How about adding the direction to your body element via a special class, then you can write according selectors:
<body class="rtl">
and in the CSS:
.rtl .myclass {
text-align: right;
}