Overriding a css property - css

My Html is like this:
<a class="another addAnother">Add another</a>
I defined a style for the above using 'another' class like this in a external style sheet.
fieldset.associations a.another {
color: #693;
display: block;
margin: 7.5px 0px 15px;
}
I am trying to override the style of tag using 'addAnother' class, like this(wherever required):
fieldset.associations a.addAnother {
display: none;
}
But I am unable to override. Any help is appreciated.
Is there any rule that while overriding a style the selector should be same(I tried this, but no avail)??

Both properties have the same importance, because both selectors are equally specific. So if the second one appears first in the CSS, it needs to acquire more importance to override one that is lower down. You could override the first one by being more specific, like this:
fieldset.associations a.addAnother.another {
display: none;
}
or
#someID fieldset.associations a.addAnother {
display: none;
}
or
body fieldset.associations a.addAnother {
display: none;
}

Both your original declarations have a specificity of 0,0,2,2. If the second declaration is below the first, it should overrule it. If it doesn't, reorder your declarations or increase the specificity.
You could add the body tag in order to increase specificity:
body fieldset.associations a.addAnother {
display: none;
}
That will increase specificity by 0,0,0,1, the minimum amount of specificity you can add.
You can also make it specific to the .another class by chaining class declarations:
fieldset.associations a.another.addAnother {
display: none;
}
That will increase specificity by 0,0,1,0.
Here is an article explaining CSS specificity. Note that the article fails to mention that !important increase specificity by 1,0,0,0, making it near impossible to overrule.

fieldset.associations a.addAnother {
display: none !important;
}

It would ultimately depend on where those two styles are in your CSS, but you can't give one more importance like this:
fieldset.associations a.addAnother {
display: none !important;
}

Related

Apply a style on element A if element B contains a certain class

Is it possible to check the class of an element, see if it exists, and then apply the style for another class?
Example pseudo code:
if (.myClass .myBlock == true) {
.otherClass {
display:none
}
}
It's not possible in this context. But you can achieve a similar result with the cascading nature of CSS.
Apply a class to the body of your website:
.another-class {
display: none; // hides .another-class by default
}
body.special-class {
.another-class {
display: block; // shows if the body contains .special-class
}
}
Since the specificity of the generated output is higher at the second rule, the elements with .another-class will be visible.
Give the following row a class
Utilising the + selector enables us to display the row after the mentioned class. This way we can style dropdowns popups, given we have the following HTML:
.popup {
display: none;
}
.popup:hover {
display: block;
}
.container:hover + .popup {
display: block;
}
<div class="container">Hover me!</div>
<div class="popup">This is a popup!</div>
I'm afraid that's all that is possible with CSS.

How to override applied CSS rules in media queries?

I use jQuery to animate my page - a function called slideToggle(). I can view this in the debugger and see the styles applied to my <nav> element.
The problem I'm facing, is that after I call slideToggle ( a second time ) it sets display:none to <nav> as it correctly should.
However, If I expand the screen again, the menu does not re-appear in its normal state as it should.
I set it in the media query but it is ignored.
#media screen and (max-width: 1000px){
/* This does nothing but I want it to turn the display on.
*/
nav {
display: block;
}
}
To answer the question can I override inline-css? ... Yes, by using !important.
Your real question:
By adding !important to your media query when the screen is big again. see following snippet (run in full screen and make screen smaller/bigger)
(function(){
$('button').on('click', function(e){
$('#test').slideToggle();
});
})();
#media screen and (min-width: 1000px) {
ul {
height:50px;
background-color: red;
width: 100%;
}
li {
display: inline-block;
height: 50px;
line-height: 50px;
float:left;
margin-left: 50px;
}
#test {
display: block !important;
}
button {
display: none !important;
}
}
#media screen and (max-width: 1000px) {
ul {
background-color: red;
width: 100%;
}
li {
display: block;
height: 50px;
line-height: 50px;
}
#test {
display: none;
}
button {
display: block;
}
}
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<div id="test">
<ul>
<li>This</li>
<li>Is</li>
<li>a</li>
<li>menu</li>
</ul>
</div>
<button >Toggle menu</button>
Media queries are irrelevant here. They don't affect the cascade at all.
Inline rules always trump rule-set rules unless the rule-set rule is !important and the inline rule is not.
In general, the most specific CSS selector will be applied to an element. The cascading order is defined as follows (highlight by me):
Find all declarations that apply to the element and property in question, for the target media type. Declarations apply if the
associated selector matches the element in question and the target
medium matches the media list on all #media rules containing the
declaration and on all links on the path through which the style sheet
was reached.
Sort according to importance (normal or important) and origin (author, user, or user agent). In ascending order of precedence:
user agent declarations
user normal declarations
author normal declarations
author important declarations
user important declarations
Sort rules with the same importance and origin by specificity of selector: more specific selectors will override more general ones.
Pseudo-elements and pseudo-classes are counted as normal elements and
classes, respectively.
Finally, sort by order specified: if two declarations have the same weight, origin and specificity, the latter specified wins.
Declarations in imported style sheets are considered to be before any
declarations in the style sheet itself.
Furthermore, you can forcefully apply a style using the !important keyword. You should not use the declaration, however, unless it is absolutely necessary after all other avenues have been exhausted. I recommend reading this article if you want to learn more about the !important keyword, when to use it and why to avoid it.
You can add a class in the media query and call addClass in your function.
By the way
You set display: block; for nav when max-width: 1000px
It should be MIN-width if you want to display the nav when the screen widens.
this will work 100%;
#media screen and (min-width: 1001px){
/* This does nothing but I want it to turn the display on.
*/
nav {
display: static !important;
}
}

Why are some print CSS rules not working?

I have this in my print CSS:
.foo
{
display: none;
}
.bar
{
display: none;
}
All class="foo" elements are hidden, but all class="bar" elements are still visible. What could be the cause of this?
CSS specificity could be overruling your print CSS rules. The simplest way to resolve this is to add !important to your rules. While generally this should be avoided, it's fine to use it in a print CSS.
.bar
{
display: none !important;
}
The other way is to make sure your print CSS rules come out on top in the specificity calculation. The exact way to do this depends entirely on your regular CSS rules.

CSS style declaration reusage

Lets say I have in my CSS a color definitions:
.headerColor { background-color: #a6c9e2; }
Now I would also like to define a CSS definition that uses .headerColor:
.header { padding-left: 2px; }
On the CSS level, how can I inherit .header from .headerColor?
I know I can place the two styles on the HTML element (class='header headerColor'), but how can I assign .header to my HTML element and have it pull its parent styles?
You can write like this:
.headerColor, .header { background-color: #a6c9e2; }
.header { padding-left: 2px; }
Now, you just need to set class="header" in HTML.

Why are my CSS properties being overridden/ignored?

I'm having some issues with the CSS "hierarchy" (not sure if it's proper to call it a hierarchy). I'm trying to style the below bit of HTML.
<body>
<section id="content">
<article>
<ul class="posts-list">
<li class="post-item">
<h2>[post title]</h2>
<p class="item-description">...</p>
<p class="item-meta">...</p>
</li>
...
</ul>
</article>
</section>
</body>
Since section#content changes on every page I have, I wanted to maintain consistent styles across all of them, so I wrote some "global" CSS rules.
#content {
color: #000;
margin-left: 300px;
max-width: 620px;
padding: 0px 10px;
position: relative;
}
#content p,
#content li {
color: #111;
font: 16px / 24px serif;
}
I wanted to style HTML within a ul.posts-list differently, so I wrote these rules.
li.post-item > * {
margin: 0px;
}
.item-description {
color: #FFF;
}
.item-meta {
color: #666;
}
However, I ran into some issues. Here is how Chrome is rendering the CSS:
For some reason, the rules #content p, #content li are overriding my rules for .item-description and .item-meta. My impression was that class/id names are considered specific and thus higher priority. However, it seems that I have a misunderstanding of how CSS works. What am I doing wrong here?
Edit: Also, where can I read up more about how this hierarchy works?
Elements id have the priority in CSS since they are the most specific.
You just have to use the id:
#content li.post-item > * {
margin: 0px;
}
#content .item-description {
color: #FFF;
}
#content .item-meta {
color: #666;
}
Basically id have the priority on class which the priority on tags(p,li,ul, h1...). To override the rule, just make sure you have the priority ;)
The "hierarchy" in which CSS rules are measured is called specificity. Each part of a CSS rule has an actual numerical base-10 value. IDs are worth 100 while classes are only 10.
For more information see http://coding.smashingmagazine.com/2007/07/27/css-specificity-things-you-should-know/
Targeting ID's is more specific than targeting classes. More specific styling will overwrite less specific styling. It should be noted that in-line styling in HTML is more specific and will therefore overwrite ID-targeted styling. In other words:
<p style="color:white" id="itemDescId" class="item-description">...</p>
With the CSS:
p{color:blue;}
#itemDescId{color:red;}
.item-description{color:green}
The text will appear white - not because it's closest to the html code, but because it's higher in the specificity hierarchy. If you remove the inline styling (and you normally should for cleaner more manageable code), then the text would become red. Remove the ID and it will be green. And finally it will be blue once the class is removed.
This is one of the more complex topics to understand in CSS, and I'm only scratching the surface, but the easiest description I've found on how CSS specificity works is over at CSS tricks:
http://css-tricks.com/specifics-on-css-specificity/
My response should have been a "comment" on the answer, but I have the correct fix although #tibo answered correctly:
li.post-item > * {
margin: 0px !important;
}
.item-description {
color: #FFF !important;
}
.item-meta {
color: #666 !important;
}
The !important rule will override the order of evaluation between id and class.
Here is a link to an article, When Using !important is The Right Choice, that will help you to understand... it made my life easier :)
Better to follow the CSS standards.
choose css selector and makeit under its parent then u may not to get conflicts when loading css fles (like .css files)

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