How to prevent styles from reaching into div - javascript

I have an interesting situation I'm trying to find a solution to.
There is a script that needs to be included that builds an HTML element on the page. The issue is that there are global defaults CSS styles that are interacting with this built element and preventing it from functioning.
So our ".core-design form" has a property that is being applied to this built element's form. None of our style needs to be used, as the script is calling in its own stylesheet.
Is there a way to prevent the div containing this element from getting any and all styles from our .core-design?
Edit: To add some clarity as to specifics.
1) The core-design class is attached to every page across many sites.
2) The sub-elements being targeted are the element names, not classes.
3) I am able to add styling to target the div around the generated content, but want to avoid modifying .core-design stylesheet due to its scope.
4) The generated content pulls in its own stylesheet.
5) I have no control over the content being pulled in, and it may change in the future.
6) Codepen of the situation I am currently in
body {
// the .core-design is applied here which contains the form styles.
}
form {
min-height:300px;
min-width:300px;
background-color:black;
}
<body>
<div class="controlled">
<div class="generated">
<form>
<!--
I need to prevent this form/generated div from inheriting any styles. Including any other sub-components inside of it. The only item I 'control' is the wrapping div.
-->
</form>
</div>
</div>
</body>

Yes, there's a way. You can use the all CSS property. More info here https://developer.mozilla.org/en-US/docs/Web/CSS/all.
There's no support for IE :(, but there are polyfills available.

This should reset all styles:
div.className * {
all: initial;
all: unset;
}

Solution 1:
Simple, it is all about CSS selector.
Add a class called ignore-this to the form you want to be ignored.
Then update the global css to have form:not(.ignore-this).
Example below, CSS applied to 1st form but skip the 2nd form.
.core-design form:not(.ignore-this) {
background: red;
}
<div class="core-design">
<form>
form 111111
</form>
<form class="ignore-this">
form 222222
</form>
</div>
Solution 2 (updated)
since you have no control over the core-design css, what you could do is to add a css rule like the following and add the class name to the form you want to reset CSS style:
form.ignore-this{
all: unset;
}
The CSS all shorthand property resets all properties, apart from unicode-bidi and direction, to their initial or inherited value.
REF: https://developer.mozilla.org/en/docs/Web/CSS/all
.core-design form {
background: red;
border: 2px solid green;
}
form.ignore-this{
all: unset;
}
<div class="core-design">
<form>
form 111111
</form>
<form class="ignore-this">
form 222222
</form>
</div>

Not so clear but i think you are having css override issues.
If you know the names of the classes and ids the div has you can change you ids and class names of the core-design so they wouldnt be the same.
Like:
if you have a class named .navi and the div contains .navi css will try to either override that of the div or that of the core depends.
Make sure your cores class and id names are unique from that of the div

Related

How to use the pseudo selectors in Inline Css in material UI? [duplicate]

I have a case where I must write inline CSS code, and I want to apply a hover style on an anchor.
How can I use a:hover in inline CSS inside the HTML style attribute?
E.g., you can't reliably use CSS classes in HTML emails.
Short answer: you can't.
Long answer: you shouldn't.
Give it a class name or an id and use stylesheets to apply the style.
:hover is a pseudo-selector and, for CSS, only has meaning within the style sheet. There isn't any inline-style equivalent (as it isn't defining the selection criteria).
Response to the OP's comments:
See Totally Pwn CSS with Javascript for a good script on adding CSS rules dynamically. Also see Change style sheet for some of the theory on the subject.
Also, don't forget, you can add links to external stylesheets if that's an option. For example,
<script type="text/javascript">
var link = document.createElement("link");
link.setAttribute("rel","stylesheet");
link.setAttribute("href","http://wherever.com/yourstylesheet.css");
var head = document.getElementsByTagName("head")[0];
head.appendChild(link);
</script>
Caution: the above assumes there is a head section.
You can get the same effect by changing your styles with JavaScript in the onMouseOver and onMouseOut parameters, although it's extremely inefficient if you need to change more than one element:
<a href="abc.html"
onMouseOver="this.style.color='#0F0'"
onMouseOut="this.style.color='#00F'" >Text</a>
Also, I can't remember for sure if this works in this context. You may have to switch it with document.getElementById('idForLink').
You could do it at some point in the past. But now (according to the latest revision of the same standard, which is Candidate Recommendation) you can't
.
You can't do exactly what you're describing, since a:hover is part of the selector, not the CSS rules. A stylesheet has two components:
selector {rules}
Inline styles only have rules; the selector is implicit to be the current element.
The selector is an expressive language that describes a set of criteria to match elements in an XML-like document.
However, you can get close, because a style set can technically go almost anywhere:
<html>
<style>
#uniqueid:hover {do:something;}
</style>
<a id="uniqueid">hello</a>
</html>
If you actually require inline code, this is possible to do. I needed it for some hover buttons, and the method is this:
.hover-item {
background-color: #FFF;
}
.hover-item:hover {
background-color: inherit;
}
<a style="background-color: red;">
<div class="hover-item">
Content
</div>
</a
In this case, the inline code: "background-color: red;" is the switch colour on hover. Use the colour you need and then this solution works. I realise this may not be the perfect solution in terms of compatibility, however this works if it is absolutely needed.
While it appears to be impossible to define a hover-rule inline, you can define the value of styles inline using a CSS variable:
:hover {
color: var(--hover-color);
}
<a style="--hover-color: green">
Library
</a>
Consider using an attribute or a class in addition to the selector (e.g., [hover-color]:hover) to allow coexistence with other low specificity hover color changing rules (from, e.g., a CSS reset or some elements using the default style).
Using JavaScript:
a) Adding inline style
document.head.insertAdjacentHTML('beforeend', '<style>#mydiv:hover{color:red;}</style>');
b) or a bit harder method - adding "mouseover"
document.getElementById("mydiv").onmouseover= function(e){this.className += ' my-special-class'; };
document.getElementById("mydiv").onmouseleave= function(e){this.className = this.className.replace('my-special-class',''); };
Note: multi-word styles (i.e.font-size) in JavaScript are written together:
element.style.fontSize="12px"
This is the best code example:
<a
style="color:blue;text-decoration: underline;background: white;"
href="http://aashwin.com/index.php/education/library/"
onmouseover="this.style.color='#0F0'"
onmouseout="this.style.color='#00F'">
Library
</a>
Moderator Suggestion: Keep your separation of concerns.
HTML
<a
style="color:blue;text-decoration: underline;background: white;"
href="http://aashwin.com/index.php/education/library/"
class="lib-link">
Library
</a>
JS
const libLink = document.getElementsByClassName("lib-link")[0];
// The array 0 assumes there is only one of these links,
// you would have to loop or use event delegation for multiples
// but we won't go into that here
libLink.onmouseover = function () {
this.style.color='#0F0'
}
libLink.onmouseout = function () {
this.style.color='#00F'
}
Inline pseudoclass declarations aren't supported in the current iteration of CSS (though, from what I understand, it may come in a future version).
For now, your best bet is probably to just define a style block directly above the link you want to style:
<style type="text/css">
.myLinkClass:hover {text-decoration:underline;}
</style>
Foo!
As pointed out, you cannot set arbitrary inline styles for hover, but you can change the style of the hover cursor in CSS using the following in the appropriate tag:
style="cursor: pointer;"
<style>a:hover { }</style>
Go Home
Hover is a pseudo class, and thus cannot be applied with a style attribute. It is part of the selector.
You can do this. But not in inline styles. You can use onmouseover and onmouseout events:
<div style="background: #333; padding: 10px; cursor: pointer"
onmouseover="this.style.backgroundColor='#555';" onmouseout="this.style.backgroundColor='#333';">
Hover on me!
</div>
According to your comments, you're sending a JavaScript file anyway. Do the rollover in JavaScript. jQuery's $.hover() method makes it easy, as does every other JavaScript wrapper. It's not too hard in straight JavaScript either.
There is no way to do this. Your options are to use a JavaScript or a CSS block.
Maybe there is some JavaScript library that will convert a proprietary style attribute to a style block. But then the code will not be standard-compliant.
You can write code in various type.
First I can write this
HTML
<a href="https://www.google.com/" onMouseOver="this.style.color='red'"
onMouseOut="this.style.color='blue'" class="one">Hello siraj</a>
CSS
.one {
text-decoration: none;
}
You can try another way:
HTML
Hello siraj
CSS
.one {
text-decoration: none;
}
.one:hover {
color: blue;
}
.one:active {
color: red;
}
You can also try hover in jQuery:
JavaScript
$(document).ready(function() {
$("p").hover(function() {
$(this).css("background-color", "yellow");
}, function() {
$(this).css("background-color", "pink");
});
});
HTML
<p>Hover the mouse pointer over this paragraph.</p>
In this code you have three functions in jQuery. First you ready a function which is the basic of a function of jQuery. Then secondly, you have a hover function in this function. When you hover a pointer to the text, the color will be changed and then next when you release the pointer to the text, it will be the different color, and this is the third function.
I just figured out a different solution.
My issue: I have an <a> tag around some slides/main content viewer as well as <a> tags in the footer. I want them to go to the same place in IE, so the whole paragraph would be underlined onHover, even though they're not links: the slide as a whole is a link. IE doesn't know the difference. I also have some actual links in my footer that do need the underline and color change onHover. I thought I would have to put styles inline with the footer tags to make the color change, but advice from above suggests that this is impossible.
Solution: I gave the footer links two different classes, and my problem was solved. I was able to have the onHover color change in one class, have the slides onHover have no color change/underline, and still able to have the external HREFS in the footer and the slides at the same time!
It's not exactly inline CSS, but it is inline.
<a href="abc.html" onMouseOver="this.style.color='#0F0'"
onMouseOut="this.style.color='#00F'">Text</a>
I agree with shadow. You could use the onmouseover and onmouseout event to change the CSS via JavaScript.
And don't say people need to have JavaScript activated. It's only a style issue, so it doesn't matter if there are some visitors without JavaScript ;)
Although most of Web 2.0 works with JavaScript. See Facebook for example (lots of JavaScript) or Myspace.
So this isn't quite what the user was looking for, but I found this question searching for an answer and came up with something sort of related. I had a bunch of repeating elements that needed a new color/hover for a tab within them. I use handlebars, which is key to my solution, but other templateing languages may also work.
I defined some colors and passed them into the handlebars template for each element. At the top of the template I defined a style tag, and put in my custom class and hover color.
<style type="text/css">
.{{chart.type}}-tab-hover:hover {
background-color: {{chart.chartPrimaryHighlight}} !important;
}
</style>
Then I used the style in the template:
<span class="financial-aid-details-header-text {{chart.type}}-tab-hover">
Payouts
</span>
You may not need the !important
While the "you shouldn't" context may apply there may be cases were you still want to achieve this. My use case was to dynamic set a hover color depending on some data value to achieve that with only CSS you can benefit from specificity.
Approach CSS only
CSS
/* Set your parent color for the inherit property */
.sidebar {
color: green;
}
/* Make sure your target element "inherit" parent color on :hover and default */
.list-item a {
color: inherit
}
.list-item a:hover {
color: inherit
}
/* Create a class to allows to get hover color from inline style */
.dynamic-hover-color:not(:hover) {
color: inherit !important;
}
Then your markup will be somewhat like:
Markup
<nav class="sidebar">
<ul>
<li class="list-item">
<a
href="/foo"
class="dynamic-hover-color"
style="color: #{{category.color}};"
>
Category
</a>
</li>
</ul>
</nav>
I'm doing this example using handlebars but the idea is that you take whatever is convenient for your use case to set the inline style (even if it is writing manually the color on hover you want)
You can just use an inline stylesheet statement like this:
<style>#T1:hover{color:red}</style><span id=T1>Your Text Here</span>
You can use the pseudo-class a:hover in external style sheets only. Therefore I recommend using an external style sheet. The code is:
a:hover {color:#FF00FF;} /* Mouse-over link */
You can do id by adding a class, but never inline.
<style>.hover_pointer{cursor:pointer;}</style>
<div class="hover_pointer" style="font:bold 12pt Verdana;">Hello World</div>
It is two lines, but you can reuse the class everywhere.
My problem was that I'm building a website which uses a lot of image-icons that have to be swapped by a different image on hover (e.g. blue-ish images turn red-ish on hover).
I produced the following solution for this:
.container div {
width: 100px;
height: 100px;
background-size: 100px 100px;
}
.container:hover .withoutHover {
display: none;
}
.container .withHover {
display: none;
}
.container:hover .withHover {
display: block;
}
<p>Hover the image to see it switch with the other. Note that I deliberately used inline CSS because I decided it was the easiest and clearest solution for my problem that uses more of these image pairs (with different URL's).
</p>
<div class=container>
<div class=withHover style="background-image: url('https://encrypted-tbn2.gstatic.com/images?q=tbn:ANd9GcQrqRsWFJ3492s0t0NmPEcpTQYTqNnH188R606cLOHm8H2pUGlH')"></div>
<div class=withoutHover style="background-image: url('http://i.telegraph.co.uk/multimedia/archive/03523/Cat-Photo-Bombs-fa_3523609b.jpg')"></div>
</div>
I introduced a container containing the pair of images. The first is visible and the other is hidden (display:none). When hovering the container, the first becomes hidden (display:none) and the second shows up again (display:block).

How can I disable all CSS that can affect my widgets on another website?

I'm building JavaScript widgets that are supposed to be added onto other people's websites.
I style my widgets by dynamically adding a CSS to the pages they're on.
For example,
My CSS code below applies to a DIV inside my widget:
.myWidget { background-color: red; }
But a CSS file outside my own on a remote page might have:
div { border: 5px solid green; }
The CSS above would also apply to my widgets. How can I disable all other CSS outside my own?
Thanks
You could be Using shadow DOM
Shadow DOM MDN Web Docs
An important aspect of web components is encapsulation — being able to keep the markup structure, style, and behavior hidden and separate from other code on the page so that different parts do not clash, and the code can be kept nice and clean. The Shadow DOM API is a key part of this, providing a way to attach a hidden separated DOM to an element.
You can use the all shorthand property and the unset keyword to set each property's value to its initial value.
.myWidget {
all:unset;
background-color: red;
}
div {
background-color:yellow;
}
<div class="myWidget">Hello World!</div>

How to override inline CSS that is already marked !important from external HTML

I am using HTML to input a cloud-based instagram feed on a website. I want to hide the bottom half of the feed that references the website of the publisher. The inline HTML that is outputting already has display: inline-block !important marked, so trying to hide it with display: none !important or visibility: hidden !important do not work. I am able to hide the entire block with CSS but not "parts" of it. I don't seem to be able to edit the HTML since it is coming from the cloud. The only HTML that I actually use on the site in order to make it render does not include any of the inline CSS, as it is only two lines.
Would someone mind explaining how this kind of thing works and why I am encountering issues overriding the inline CSS?
I have tried using:
display: inline !important, display: none !important and visibility: hidden !important
None of these are receiving priority, as the element.style in the chrome developer console clearly shows the inline CSS already marked as !important that I do not have access to, nor can I edit.
I simply want to hide one selector within the HTML. It is marked as "a"
a {
}
I have tried using this selector within the actual element, but it does not receive priority either. Nothing is working.
Try to remove the inline style with jQuery
$("#myDiv2").css("transform","");//used rotate to see the effect
<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/1.8.3/jquery.min.js"></script>
<div id="myDiv1" style="width:100px !important; height:100px !important;transform:rotate(30deg) !important">
//Some Content
</div>
<div id="myDiv2" style="width:100px !important; height:100px !important; transform:rotate(30deg) !important">
//Some Content
</div>
Setting the value of a style property to an empty string removes that property from an element.
$("#myDiv2").css("transform","");
Typically the only way to do this is to be more specific in your selector, for example selecting a[href][style] is more specific than just a. But since this is inline styles and already using !important you unfortunately might be out of luck!
a[href][style]{
color: green !important;
}
This link uses !important
<br/>
This link does not
If you wanted to just remove the links without importing several thousand lines of jQuery code, you can select and remove all <a> tags with just a few lines of plain JS.
document.querySelectorAll('a').forEach(link => {
link.remove();
});
<p> here is some text
This link uses !important
<br/>
This link does not
and some more text
</p>

remove / reset inherited css from an element [duplicate]

This question already has answers here:
How to reset/remove CSS styles for a specific element or selector only
(17 answers)
Closed last month.
I know this question was asked before, but before marking it as a duplicate, I want to tell you that my situation is a little different from what I found on the internet.
I'm building and embedded script that people can put it on their sites. This script creates a div with a certain width/height and some information in it.
My problem is that some websites declare styles for div that are inherited by my div as well.
for example:
div{
background-color:red;
}
so if I don't set any background color to my div, it will show red even if I don't want that.
The only solutions I come along is to overwrite as many css proprieties, this way my div will show exactly as I want.
The problem with this solution is that there are too many css proprieties to overwrite and I want my script to be as light as it can be.
So my question is if you know another solution to my problem.
It can be in css/javascript /jQuery.
Thanks
"Resetting" styles for a specific element isn't possible, you'll have to overwrite all styles you don't want/need. If you do this with CSS directly or using JQuery to apply the styles (depends on what's easier for you, but I wouldn't recommend using JavaScript/JQuery for this, as it's completely unnecessary).
If your div is some kind of "widget" that can be included into other sites, you could try to wrap it into an iframe. This will "reset" the styles, because its content is another document, but maybe this affects how your widget works (or maybe breaks it completely) so this might not be possible in your case.
Only set the relevant / important CSS properties.
Example (only change the attributes which may cause your div to look completely different):
background: #FFF;
border: none;
color: #000;
display: block;
font: initial;
height: auto;
letter-spacing: normal;
line-height: normal;
margin: 0;
padding: 0;
text-transform: none;
visibility: visible;
width: auto;
word-spacing: normal;
z-index: auto;
Choose a very specific selector, such as div#donttouchme, <div id="donttouchme"></div>. Additionally, you can add `!important before every semicolon in the declaration. Your customers are deliberately trying to mess up your lay-out when this option fails.
You could try overwriting the CSS and use auto
I don't think this will work with color specifically, but I ran into an issue where i had a parent property such as
.parent {
left: 0px;
}
and then I was able to just define my child with something like
.child {
left: auto;
}
and it effectively "reset" the property.
Technically what you are looking for is the unset value in combination with the shorthand property all:
The unset CSS keyword resets a property to its inherited value if it inherits from its parent, and to its initial value if not. In other words, it behaves like the inherit keyword in the first case, and like the initial keyword in the second case. It can be applied to any CSS property, including the CSS shorthand all.
.customClass {
/* specific attribute */
color: unset;
}
.otherClass{
/* unset all attributes */
all: unset;
/* then set own attributes */
color: red;
}
You can use the initial value as well, this will default to the initial browser value.
.otherClass{
/* unset all attributes */
all: initial;
/* then set own attributes */
color: red;
}
As an alternative:
If possible it is probably good practice to encapsulate the class or id in a kind of namespace:
.namespace .customClass{
color: red;
}
<div class="namespace">
<div class="customClass"></div>
</div>
because of the specificity of the selector this will only influence your own classes
It is easier to accomplish this in "preprocessor scripting languages" like SASS with nesting capabilities:
.namespace{
.customClass{
color: red
}
}
Try this: Create a plain div without any style or content outside of the red div. Now you can use a loop over all styles of the plain div and assign then to your inner div to reset all styles.
Of course this doesn't work if someone assigns styles to all divs (i.e. without using a class. CSS would be div { ... }).
The usual solution for problems like this is to give your div a distinct class. That way, web designers of the sites can adjust the styling of your div to fit into the rest of the design.
As long as they are attributes like classes and ids you can remove them by javascript/jQuery class modifiers.
document.getElementById("MyElement").className = "";
There is no way to remove specific tag CSS other than overriding them (or using another element).
you may use this below option.
<style>
div:not(.no_common_style){
background-color:red;
}
</style>
now , if their any place where you do not want to apply default style you can use 'no_common_style' class as class.
ex:
<div class="no_common_style">
It will not display in red
</div>
From what I understand you want to use a div that inherits from no class but yours. As mentioned in the previous reply you cannot completely reset a div inheritance. However, what worked for me with that issue was to use another element - one that is not frequent and certainly not used in the current html page. A good example, is to use instead of then customize it to look just like your ideal would.
area { background-color : red; }
One simple approach would be to use the !important modifier in css, but this can be overridden in the same way from users.
Maybe a solution can be achieved with jquery by traversing the entire DOM to find your (re)defined classes and removing / forcing css styles.

Show just particular parts of website - select via CSS?

what would be the easiest method to display only specific elements on a website?
For example, on a news site only the headlines and nothing else.
I'd like to select elements via CSS so only those should be displayed.
I tried to use the :not pseudoclass:
:not(.myClass) { display: none; }
But obviously, the parents of the .myClass-elements aren't displayed and so aren't them.
Do you know any possibility to achieve this? It doesn't have to be CSS-only, Javascript is possible too.
A web-app that does this would also be great.
I'd like to be able to filter some sites I visit, so I would apply this as a user-stylesheet.
You can load the page with jQuery and easily select the elements you want...
$("body").load("path/to/page.html div.headline");
The above will load all <div class="headline"> elements into the body of the document.
Note: You will of course have to keep the same origin policy in mind.
If you want to show only the news headline you will need to structure your HTML correctly. If you have a container div the easiest way to do this would be to apply a secondary class to it and show/hide elements trough that class:
<div class="container news_page">
<h1>Title</h1>
<p>Random text I want to hide.<p>
<div class="random_container">Another random element i want to hide.</div>
</div>
.container {border:1px solid red;} /* .container has normal styling */
.news_page p, .news_page .random_container {display:none;} /* .news_page is used only to select elements inside container on news page */
This would be the css only solution to this.
I can't figure out how to comment on things, so as a response to the last answer's last comment, check this out: http://selectivizr.com/. It says it can emulate CSS3 selectors for IE, so maybe that will fix your problems with Exploder...

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