I have a CSS file called lightbox.css on my website that I link to via my header.
I would like to avoid render-blocking and have looked up media queries as a method - however, what I would like is to ensure that the CSS loads once the user scrolls down (but after page load). That way I assume it will not be render-blocking, while at the same time it will be available for the parts of the website where it is needed.
Is this possible?
I have a site that has multiple pages. The first page is just a listview with icons and links to the other pages. CSS stylesheets work fine on the first page, but when I go to one of the linked pages, my custom css stylesheet (and js for that matter), related to that page, is being ignored. If I look in the FF inspector I see that it has dropped the associated lines that tell it about my stylesheet. If I directly go to the desired page or if I hit refresh, the styles look fine, but whenever I come from a link off the first page, the styles are gone. I see no errors when loading the page. Is this a know issue? How can I force it to not ignore my stylesheets.
I am using jquery mobile 1.4.5 in addition to my own.
Looking further. It looks like hitting the link is appending the body of the 2nd page at the end of the first and not simply loading the 2nd page.
It turns out that by default links behave a little different than normal when using jQuery Mobile. The don't do a full page load, but instead only inject the part contained in a div marked with data-role="page". I did not know this.
http://demos.jquerymobile.com/1.1.1/docs/pages/page-links.html
I have a site whose stylesheets are becoming overwhelming, and a full 50% to 90% or so is not used on certain pages. Rather than have 23 separate blocking CSS sheets, I'd like to find out which are being used on the page I'd like to target, and have those exported into one sheet.
I have seen several questions that recommend "Dust me selectors" or similar add on which will tell what selectors are and are not being used; but that's not what I want. I need to be able to export all used styles from all sheets for that particular page into one new sheet that can be used to replace the 23 others. The solution should be able to support a responsive website (media calls). The website page I'm targeting is: http://tripinary.com.
I've found: https://unused-css.com but this is a paid service and I need free;
The next closest thing I've come across is http://www.csstrashman.com/ but this does not look at stylesheets. In fact, it completely ignores them and ultimately I'm having trouble with the responsiveness of the site. Many times as well, this site just crashes.
I don't mind a programmatic solution if someone has had to do this before and can recommend a direction.
(deleted my comment to RwwL answer to make it a thorough answer)
UnCSS, whether node.js or as a grunt or gulp task, is able to list used CSS rules by an array of pages in an array of Media Queries.
uncss: https://github.com/giakki/uncss
grunt-uncss: https://github.com/addyosmani/grunt-uncss
gulp-uncss: https://github.com/ben-eb/gulp-uncss
Multipage:
You can pass files as an argument to any of the 3 plugins, like:
var files = ['my', 'array', 'of', 'HTML', 'files'],
options = { /* (…) */ };
uncss(files, options, function (error, output) {
console.log(output);
});
Avoid:
urls (Array):
array of URLs to load with Phantom (on top of the files already passed if any).
NOTE: this feature is deprecated, you can pass URLs directly as arguments.
Media Queries and responsive are taken into account:
media (Array):
By default UnCSS processes only stylesheets with media query "all", "screen", and those without one. Specify here which others to include.
You can add stylesheets, ignore some of them, add inline CSS and many other options like htmlroot
Remaining problems:
1/ Conditional classes if you use them for IE9-. They obviously won't be matched in a WebKit PhantomJS environment!
HTML:
<!--[if IE 9]><html class="ie9 lte-ie9" lang="en"><![endif]--> <!-- teh conditional comment/class -->
CSS:
.ie9 .some-class { property: value; ] /* Only matched in IE9, not WebKit PhantomJS */
Should they be added by hand or script to the html element in testing environment? (how it renders is of no importance)
Is there an option in uncss?
As long as you don't style with :not(.ie9) (weird), it should be fine.
EDIT: you can use the ignore option with a pattern to force uncss to "provide a list of selectors that should not be removed by UnCSS". Won't be tested though.
2/ Scripts that will detect resolution (viewport width) and adapt content to it by removing/adding it or adding a class on a container. They will execute in PhantomJS in desktop resolution I guess and thus won't do their job so you'll need to modify calls to PhantomJS or something like that... Or dig into options or GitHub issues of the 3 projects (I didn't)
Other tools I heard of, not tested or barely or couldn't test, no idea about the MQ part:
in grunt-uncss readme, the Coverage part
ucss from Opera (there's already an ansswer here, couldn't make it work)
Helium
CSSESS
mincss
Addy Osmani has countless presentations of 100+ slides presenting awesome tools like this one: https://speakerdeck.com/addyosmani/automating-front-end-workflow (you'll regret even more that days are made only of 24 hours and not 48 err wait 72 ^^)
How about the CSS Usage plugin for Firebug?
Steps:
Visit your page in Firefox
Click "CSS Usage" tab in Firebug
Click the Scan button
Click the bold file name
Save page of CSS selectors to disk
Here are some screen shots and walk through. Not sure about media queries or if it'll work on your site, and it'll probably not keep -webkit etc, but maybe it'll get you part of the way there.
Opera Software released a CSS crawler on Github that claims it can find unused and duplicate selectors. It might do the trick if you're comfortable with a command-line tool. https://github.com/operasoftware/ucss
You Can Check in Google Chrome by doing inspect element (F12) . The unused CSS has Line over the tags.
If you wanted, you could try to build a script that runs on a (non-production) server that goes through every css rule, removes it from the stylesheet, loads the page using something like phantomjs, and checks to see if anything changed from the last time it loaded the page. If so, then put the css rule back, if not, then leave it out and move on to the next rule. It would take a while to run, but it would work. You would also have to setup an instance of your server that does not use caching for it to run on.
Try using this tool,which is just a simple js script
https://github.com/shashwatsahai/CSSExtractor/
This tool helps in getting the CSS from a specific page listing all sources for active styles and save it to a JSON with source as key and rules as value.
It loads all the CSS from the href links and tells all the styles applied from them
You can modify the code to save all css into a .css file. Thereby combining all your css.
Using developer tools, I can amend a css file for a site I'm currently viewing in a browser.
I want to, effectively, do the same - but instead of amending the css file, loading a local css file, just for that particular domain.
Another way of phrasing it: "When any page of stackoverflow.com is loaded, load C:\test.css to the browser".
Yes, it's possible. Have a look at http://userstyles.org.
Userstyles.org offers CSS files for usage with the extension "Stylish", and Stylish recently announced that they are becoming evil (https://forum.userstyles.org/discussion/comment/109966/#Comment_109966) and can therefore not be used anymore.
One can use the styles with greasemonkey, but then the activation for various websites doesn't work anymore (the CSS is converted into a JS file and the list of sites where it should be applied onto is hardcoded inside an if-statement in that script). I.e. in order to use e.g. "dokuwiki highlight and full width" on a site using dokuwiki but not being http://dokuwiki.org, you have to edit that if-statement and reload.
Is there a way to specify a certain chunk within a custom css stylesheet for a browser to apply to different websites or URLs? For example, Google Chrome's Custom.css or Firefox's userContent.css can be modified to change the appearance of a website, but the changes will apply to every website you visit that share the same tags, id's, classes, etc. Like includes or something?
For Firefox, you can do this using https://developer.mozilla.org/en-US/docs/CSS/#document (needs a -moz prefix at the moment, since it's non-standard).
Chrome and Firefox have defined their own css to be a "default" for rendering certain page elements. This is part of the browser, which is why they can let it be global. You, on the other hand, don't have that privilege.