Make entire CSS sheet !important - css

Is there a way to make an entire CSS Style sheet take precedence over another? I know you can do the !important but can I do that with one line rather than modify all thousand properties on the sheet?
Thanks!

Make sure the stylesheet you want is called last (or a specific style you want is called last). For example, using this:
span { color: red; }
span { color: blue; }
...will turn all text in <span>'s blue. Take a look here.

Rules with identical specificity that come later will overrule previous ones, so if both style sheets contain the identical selectors, you should be able to do this by just loading the one before the other.
If they contain different selectors, like
#navigation h3 { color: red }
and
.mainpage .navmenu h3 { color: blue }
you are likely to get specificity conflicts. The only blanket solution for that is indeed !important (although that is really, really terrible architecturally. Are you sure you need this? Maybe explain why, it's possible somebody is able to come up with a better solution.)
There is, however, no single-line directive to elevate the "importance" of one style sheet over the other.

Related

Is it proper syntax to "nest" id declarations inside other id declarations in CSS?

So, I'm not sure what I've stumbled upon here. I'm working with some CSS and I know it is common place to do something like this:
#content{
/* Style the content div. */
}
#content p{
/* Style all p elements in the content div. */
}
I'd like to give one specific p element a float:right style. Only one such p element will occur in the content element. Naturally, I'd just give this element an id, but then I had the idea to do it this way:
#content #right_floating_p{
float:right;
}
This works when I run the code, but I was wondering about best practice and whether or not this actually does anything scope wise. I could just as easily define a separate id for right_floating_p, but to me it feels natural that it should be defined with the content id because it will be used only on one p element inside the content element.
If anyone has any information about this syntax, please let me know. Thanks!
My recommendation is to only include the last ID. This is fairly standard separation of concerns. What if you want to change the first ID #content, but the last one #right_floating_p still makes sense and shouldn't change? There is more room for error if you specify something unnecessarily.
Other reasons this is good:
Smaller, faster (but barely) download size for your users.
More readable, in my opinion.
Faster (but barely) performance.
Over-qualifying tags is bad practice in general, as far as performance goes. Browsers read your selectors from right-to-left, by the time it interprets your #content selector, that information is pointless. My advice is to not trust that the browser will optimize for this.
Alvaro nailed it in his comment above.
The id must be unique on the page, but not necessarily across the whole site. So, for instance, if you had the #right_floating_p element on every page, but it had a #content element as an ancestor only on a certain page where you wanted it styled differently, then you'd want to use the #content #right_floating_p selector to apply the context-specific style.
I would suggest only using the most precise selector as you can, not only for readability and file size, but also for specificity.
CSS selectors have a specificity to them, so if you were to override it later (such as with a media query), the more specific selector will override the less specific one.
#content #right_floating_p {
color: red;
}
div #right_floating_p {
color: green; /* Will not apply, as it's less specific */
}
p {
color: black; /* Even less specific */
}
It will work having the first selector, but it's not necessary.

Priorizing CSS properties

I am building websites for a while, and I have a question about CSS I can't really rid over. So there is that frequent situation when multiple classes affect a DOM element, and both classes declare the same properties. For example:
.first {
color:white;
}
.second {
color:black;
}
I know that if I have an element with class="first second" in that the text will be black. If I rather want it to be white, I have several options:
Using !important: I know this one is handy and I use it, but sometimes, if I use it too often, my CSS may become messy. I mean, multiple !important's can result the same basic situation.
Reordering the classes inline: if I am correct, which class comes first, it will be the priority one. This is nice, but i often work with environments where I can't affect that. Secondly, this is not a global but a local solution.
Reorder the CSS itself: well, this sounds interesting, but if I work with many stylesheets (and I do), it is hard to track, especially when it is WIP.
Actually what I am looking for is some workaround like z-index but for priorizing which class is stronger. Because I can't really find anything useful in this topic, I am just curious maybe it is a user error, and you guys know something I don't. How do you manage this? What do you suggest?
class="first second" is the same as class="second first". The priority is based on the position of the declarations in your css and not in their position on the html element.
So, if you want priority of a class against another, put the top priority class LAST on the css file.
.first {
color:white;
}
.second {
color:black;
}
in this example, class second has always priority over class first. This happens because browser scans through the css top-to-bottom and always applying the rules of matched classes that finds. So, the last matched class has priority over the previous matched classes.
see this fiddle: http://jsfiddle.net/5c29dzrr/
At the same specificity level, the CSS selector that is furthest down the stylesheet will be applied. So in your example, if you wanted in that situation to have the element with the white colour you would have to order your properties like so:
.second {
color: black;
}
.first {
color: white;
}
The order of the classes in the HTML tag is not important; it is the order in which they appear in your CSS.
The better way to handle this is to go with some better naming convention such as BEM or SMACSS so that you don't have the issue of conflicting class names.
Edit: It might be worth reading up on specificity and the cascade for a better understanding of this. I found this calculator to be pretty handy in determining which rules will take precendence, although these days you can just use the developer tools to find out that information.

Is there a way to apply a CSS class from within a style?

I'm trying to be more modular in my CSS style sheets and was wondering if there is some feature like an include or apply that allows the author to apply a set of styles dynamically.
Since I am having a hard time wording the question, perhaps an example will make more sense.
Let's say, for example, I have the following CSS:
.red {color:#e00b0b}
#footer a {font-size:0.8em}
h2 {font-size:1.4em; font-weight:bold;}
In my page, let's say that I want both the footer links and h2 elements to use the special red color (there may be other locations I would like to use it as well). Ideally, I would like to do something like the following:
.red {color:#e00b0b}
#footer a {font-size:0.8em; apply-class:".red";}
h2 {font-size:1.4em; font-weight:bold; apply-class:".red";}
To me, this feels "modular" in a way because I can make modifications to the .red class without having to worry so much about where it is used, and other locations can use the styles in that class without worrying about, specifically, what they are.
I understand that I have the following options and have included why, in my fairly inexperienced opinion, they are less-than-perfect:
Add the color property to every element I want to be that color. Not ideal because, if I change the color, I have to update every rule to match the new color.
Add the red class to every element I want to be red. Not ideal because it means that my HTML is dictating presentation.
Create an additional rule that selects every element I want to be red and apply the color property to that. Not ideal because it is harder to find all of the rules that style a specific element, making maintenance more of a challenge
Maybe I'm just being an ass and the following options are the only options and I should stick with them. I'm wondering, however, if the "ideal" (well, my ideal) method exists and, if so, what is the proper syntax?
If it doesn't exist, option 3 above seems like my best bet. However, I would like to get confirmation.
First of all you cannot do apply-class:".red";
to perform this type of action i will suggest you to use this method
.red {color:#e00b0b;}
h2 {font-size:1.4em; font-weight:bold;}
.mymargin{margin:5px;}
<h2 class="red mymargin">This is h2</h2>
and to use in div
<div id="div1" class="red mymargin"></div>
In this case if you will change in .red class.it will be changed everywhere
Short answer: There's no way to do this in pure CSS.
Longer answer: Sass solves this problem via the #extend directive.
.error {
border: 1px #f00;
background-color: #fdd;
}
.seriousError {
#extend .error;
border-width: 3px;
}
This lets you keep your CSS modular in development, though it does require a precompilation step before you use it. It works very nicely though.
You can use the DOM in javascript to edit the id and/or class attributes of HTML tags dynamically.
I agree with DarthCaesar and jhonraymos. To update a class using JavaScript, all you would need is a simple:
function toggleColorClass(e){
var redClass = document.getElementsByClassName('red');
redClass.removeAttribute('class', 'red');
/*Set the class to some other color class*/
redClass.setAttribute('class', 'blue');
}
Of course, to make this work, you would need to include the above function in your document somewhere... if this is all the JS you're using you can probably stick it in the head or even use it inline. You would probably also want to write it so that the toggle goes in both directions, i.e. turning red on and off. Furthermore, jhonray's snippet is probably how you would want to mark up your CSS.

Is it a good idea to use !Important in a CSS file

I have lots of CSS files on my current project, and a lot of the styles in these files have !important besides them. A feeling inside me tells me that this is not a good thing. Can someone shed some light on what happens when we use !important and whether it is a good idea or not.
thanks,
Sachin
!important means the rule cannot be overridden. Take note that user stylesheets using !important will override author stylesheets.
http://www.w3.org/TR/CSS21/cascade.html#important-rules
Whether this is bad or good really depends on the usage. I don't use this keyword often myself. One example is that it allows me to override styles pulled in from 3rd party widgets/plugins.
!important gives a style precedence and will ensure (where it can) that it is the style used. If you are using !important because your selectors just aren't specific, or well thought out, enough, then that's not the way they should be used. For me, there more useful for when you may have to deal with styles you have no control over.
To illustrate, where you might want to use `!important, you might have two stylesheets. One 'global' , that you have control over and one 'local', that you do.
In the global stylesheet, you might have the following:
p span {
color: black;
}
In the local one, you could override this by doing:
p span {
color: red;
}
This might work, but if the local one is included before the global one, there will be a conflict and the global styles will take precedence. To overcome this, you can do:
color: red!important;
In the case where you could just be more specific with your selectors, it would be better to do that, rather than use !important.
Global, all spans are black:
span {
color: black;
}
In local, spans inside paragraphs are red:
p span {
color: red;
}
There's nothing 'wrong' with using !important really, I guess it's a case by case scenario, but hopefully the above explains how to make the best use of them.
Some more discussion on 'When using !important is the right choice' over on CSS tricks.

How do you read !important in CSS? [duplicate]

This question already has answers here:
What does !important mean in CSS?
(5 answers)
Closed 3 years ago.
How is the CSS attribute property !important read?
Is it really important, exclamation mark important, ...?
Answer: From the answers below, it seems to be read simply important, or bang important.
an "!important" declaration (the delimiter token "!" and keyword
"important" follow the declaration) takes precedence over a normal
declaration.
http://www.w3.org/TR/CSS2/cascade.html#important-rules
Basically, where two style rules are the same... it gives the one marked !important greater importance and will apply those styles.
Example
div{
opacity:0 !important;
}
div.jason{
opacity:1;
}
The first rule would be applied even though the second rule is more specific (one element + one class as opposed to one element)
Note: IE6 ignores !important when you have two of the same property and one of them is important - it'll always apply the last declaration, whether or not it was marked important. **Added from #BoltClock's comment below.
Warning: !important is a hammer that should only be used when absolutely necessary. Almost always, it is better to use more specific selectors to achieve greater specificity and have your styles applied the way you want. !important can make it very difficult for future developers to find and make changes to your code.
One good use case: !important is great for user-defined styles, where a user wants to manipulate Web site pages in specific way in his browser (say make all the backgrounds black and the text yellow). Without having to worry about specificity, the user can add styles to certain elements (like body) and make the styles render.
Just "important" or "bang important." The ! is definitely not a negation in this case.
It's not a tag, it's a keyword.
body { color: red !important; } means, in English, "The text-color of red is important".
In terms of how CSS sees it, it applies more "weight" to that declaration, so it will be (far) more likely to be the applied style.
For an example of this, we can use
p { color: red; }
p.blue { color: blue; }
Now, any p with a class of blue will show blue text, all the others will show red text.
If we change it to this...
p { color: red !important; }
p.blue { color: blue; }
They will all show red text (even if they have a class of blue), as we've given more important to the first selector.
I like to think of it as "NOT important".
p {
color: red !important; /* The rest is NOT important for this CSS property. */
}
Meaning that everything else from that declaration and on is NOT important and should not be taken into account. The idea came from the usage of the "!" character as a boolean NOT in many programming languages. This way the !important makes sense as you read it.
I guess I read the ! as "very".
p { color: red !important }
I read as "Paragraphs have the color red, which is very important.

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