I saved and am using the bootstrap css but it conflicts with my main css.
it has tags body, html, a, img, p... and my css loses configuration
how can I use the bootstrap css without colliding?
thank you
Try importing your custom CSS after Bootstrap CSS.
In CSS, the “!important” suffix was originally intended to provide a method of overriding author stylesheets. Users could define their own “user stylesheets” and could use this suffix to give their rules precedence over the author’s (website creator’s) styles.
Unfortunately, and quite predictably, its usage has spread massively, but not in the right direction. Nowadays, it’s used to counteract the pain of having to deal with CSS specificity, otherwise known as the set of rules which dictate that “div h1 a” is more specific selector than “div a”. Most people that use CSS on a daily basis don’t know enough about CSS specificity to solve their problems without using the “!important” suffix.
1.over ride those styles in your css file by using !important property. bootsrtap css either override or extend your css with bootstrap css so if you want to override entire css of some class best to use !important property.
2.if your are using script in your code so its very easy to differentiate the css styles.
Try combining into one CSS, multiple CSS slows down the sites.
Even, Bootstrap has its own body,html, etc tags. You have to edit them or delete/comment them. So it avoids conflicts.
Generally, the last CSS property will be applied, so if you put your body, html etc at the end of Bootstrap.css, that might work, but not recommended.
Related
I have some h1, h2, h3 and a lot of bootstrap snippets that I want to apply only to a specific part of my site, I added a unique class, say .unique but it would take hours to prefix over 1000 of CSS lines
I use sublime text
Thanks in advance
You could use a CSS-preprocessor like LESS or SASS (there are more). Both can do what you want, by just doing this:
.unique {
// Old CSS goes here
}
The have many other advantages over normal CSS.
common I would like to give you some ideas, cause i think your question has something to do with control css overriding.
the Jost's LESS or SASS solution is very good actually to prefix cause can use nested css features, but it requires a compile process, their eventually compiled files are still css. cause the .less or .sass files can not be recognized for html to render styling.
Another thinking To avoid css conflicts and wrong overriding,
Instead of including global styling, see if you can embed them in part of the specific section/page where they can get higher priorities than the rest global styles.
even the same css, generally, !important > inline css > internal css > external css
or javascript can trigger css override after previous css finished rendering on the page.
Instead of using css priorities or script running priorities to override styles, making two external mobile.css, destop.css for example, then using javascript to reload page to include different stylesheet when device width are detected to have been changed in browser resizing behavior.(This is one pop way used in responsive view)
using IDE to locate css patterns and replace them with your prefix if it's simple to match all the patterns.
When a JavaScript library creates a <div>, it typically sets a class on the div so that the user of the library can style it him/herself. It's also common, however, for the JS library to want to set some default styles for the <div>.
The most obvious way for the library to do this would be with inline styles:
<div style="application's default styles" class="please-style-me">
...
</div>
However, this will make the application's default styles trump the user's styles. A workaround is to use nested divs:
<div style="application's default styles">
<div class="please-style-me">
...
</div>
</div>
This works great for many styles like 'font' but fails for others like 'position', where the inner div's style will not override the outer div's.
What is the best practice for creating user-stylable elements with defaults in a JavaScript library? I'd prefer not to require users to include a CSS file of defaults (it's nice to keep your library self-contained).
When a JS library has a default set of styles that should be used, but should also be overridden, the JS library should include a separate stylesheet.
JavaScript should avoid adding styles directly as much as possible, and defer all styling to CSS where it's reasonable.
It's common for sets of styles to be toggled on and off. The way to elegantly handle these situations are with CSS classes.
A case where it may not be reasonable to simply use external stylesheets is animation. CSS animations could certainly be used, but for cross-browser support, asynchronous interpolation is used to animate styles from one value to another.
There isn't !notimportant or !unimportant in CSS. And I haven't run into an accepted best practice. It seems like a CSS file is the defacto standard for styles that should be user modifiable.
But if you want to keep things all in one library, I would take your second example, with your application default styles, then append a CSS class to it and prepend something unique to the class name. Then if the implementor wants to override your styles, the implementor could just use !important to override your user styles.
Adding !important to one or two styles in a CSS file shouldn't be a huge deal, but if you're creating a bunch of inline styles, this may not be the best solution.
What's a good way to create a no-conflict version of a CSS stylesheet? Let's say you have a bunch of code with classes that overlap with Bootstrap's classes.
Is this valid: adding a class="bootstrap" to the ancestor element under which bootstrap styles should be applied, and then changing bootstrap.css to prefix every rule {} with .bootstrap rule {}?
I've also needed to do this recently with the bootstrap form styles to avoid clashes, and I've found that you can surround all the #imports in the bootstrap.less (or your own custom version) with: .bootstrap { ... } and rebuild bootstrap. Now every CSS selector will be prefixed with .bootstrap.
I don't see any reason that would not work, but there are probably some performance implications to doing that - I'm not sure if they would even be significant enough to consider. It would probably be a better idea to rename the conflicting classes.
Here are a couple of resources to check out:
http://www.vanseodesign.com/css/css-selector-performance/
https://developer.mozilla.org/en/Writing_Efficient_CSS
And this is from Mozilla's CSS efficiency guidelines (2nd link): "This is the key to dramatically increasing performance. The fewer rules required to check for a given element, the faster style resolution will be."
Yes. That is an ugly approach and you will get into DOM Bashing (slower performance). Is there any reason why you couldn't just refactor your code and seperate the bootstrap styles entirely?
I have a simple HTML page that is referencing 3 CSS files. The first is a style sheet that is just for the page. The other two are for the styles of two unique modals. These modal CSS files were not created by me and they are happily being used separately on other pages throughout the site.
My problem is that both of these modal CSS files contain a few common selectors and so they are messing up each other's styles.
I understand that the best way to fix this problem is to take one or both of the files and make their selectors unique. One way would be to namespace the selectors.
My questions is, however, now that I'm knee-deep in this page, is there anyway to prevent these CSS conflicts without changing the modal CSS pages as they currently stand? Are there any tools that can help such as LESS? What is the best practice for preventing this in the future?
The best solution indeed would be to refactor those css-files to your need.
However, an easier solution would be to include your stylesheet after those two third-party css-files and re-declare the styles for the common selectors, which automatically overrides the previous settings.
LESS/SASS are excellent tools to help you write CSS faster and more comfortable. I use SASS for private work and really recommend it. They can't help you though with issues like you have atm.
EDIT:
Using !important is possible, but considered bad habit, as it was intended to give the user the possibility to override author-styles with his own. Instead of using !important what you should do is:
Avoid duplicate styles as much as you can.
if you can't avoid this, try to resolve this by either:
cascading (=using the proper sequence to override previous styles)
using selector specificity (W3C-Spec).
Assuming:
...
<link rel="stylesheet" href="this_page.css" />
<link rel="stylesheet" href="modal_1.css" />
<link rel="stylesheet" href="modal_2.css" />
...
Due to the cascading nature of CSS (sorry, I had to) using the same selector over and over overrides any previous styles. Thus, if modal_1.css and modal_2.css both apply style x to the body tag, for example, the second stylesheet will override the first.
The sad part is that there is no way out other than to, as you suggested, modify the two selectors to make them more specific.
Looking to the future, the best way to avoid overriding previously declared styles, is to always be specific about the particular element you are targeting, and it's proper place in the DOM. Note that LESS is simply a CSS preprocessor, which only allows you a different syntax for CSS.
I would suggest to a common class add into body tag of that particular page & target using that particular class. If you tools like LESS or Compass you can easily achieve the aim.
.pageOne{ /*All the styles for this perticular page*/
.header{
}
.sidebar{
}
}
When parse through LESS or Compass it will look like following.
.pageOne .header{}
.pageOne .sidebar{}
This way your page will get a namespace.
I'd like to import an external CSS (eg. Bootstrap) into my site-- the problem is I'd like to apply the Bootstrap styles only to a specific region of the page. When I include Bootstrap, it applies its styles to the entire page, restyling all tables, divs, etc.
Is it possible to only apply Bootstrap to a region (say a parent div or something?)
Thanks
The only way to do this is to have a separate iframe for the content you want to style with Bootstrap (unless you want to edit the Bootstrap CSS, and add your outer div's selector to the beginning of EVERY rule).
HTML5 introduced the new scoped attribute, which is made specifically for your use case, but has not yet been implemented by any one of the major browsers.
If you are using jQuery (which you probably are, since all of Bootstrap's Javascript functionality is dependent upon jQuery), you might wanna try Simon Madine's jQuery Scoped CSS plugin.
Import Bootstrap before your own styles. That way your own styles will overwrite the changes made by Bootstrap where applicable.
I've only tried this locally and not given it any thorough testing but it seems to work fine. I created a div around the content and assigned it an id. Then prefixed all of the bootstrap selectors with the id I assigned the surrounding div. The prefixing was done with a couple of search and replace operations. Perhaps it can be done easier with less
Forgot to mention that the body selector of the bootstrap.css has to be replaced with the id and not prefixed like the other selectors.