I'm a web developer, not an CSS expert. We recently started using Angular and I'm wondering what is the best practice applying styles in Angular templates.
Discussion we have at work is whether to use external CSS files or internal style tags. We do not have too many templates and each template mostly has its own unique styles. We are debating between external CSS files and/or internal styles.
Couls someone provide an expert opinion on this subject.
Internal styles are only applicable to the page that includes them. As such, if you want to update common styling (such as a menu) on multiple pages, you'll need to update each page individually.
Considering you'll almost definitely have certain styles apply to elements on more common to more than than one page, you'll definitely want to opt for external stylesheets. This allows pages A and B to both inherit styles from a single style.css or similar file.
This way, you can load all the relevant styles with a single line of code in the <head> of each page:
<link href="style.css" rel="stylesheet">
And you only have to update style.css when you want to update multiple page's styling.
Angular brings scoped CSS from v1.5 up (when components were introduced - I believe). It's a good concept but, in small to medium apps, the difference is hardly noticeable. You should only consider using scoped CSS in conjunction with a tool that knows how to make the best of it (i.e. Webpack).
If you're not using Webpack, just stick to the classic model: one big style-sheet.
Note that technically, regardless of stack, if you want to provide the best possible experience (fastest loading times without FOUC) you want to put all the above-the-fold and general layout-ing styles inline, preferably in a head <style> tag and everything else inside a stylesheet loaded asynchronously.
Read this article about loading CSS async.
Related
So I've recently started making more use of EJS templates in my website and so I've done things like broken out the top nav bar and other things into their own template. Is there a standard practice for how to organize CSS (or more specifically SCSS) with that? Should I just make a matching SCSS for each template with just the styles for that template and add the <link/> in each page that uses the template? Or just I just add <style/> tags to the template itself with the CSS in there. Is there a standard pattern for this?
Good question. I think the answer is "no", there is no universally best or accepted standard.
The advice my "work-mentor" always gives me is good advice: he says "do what will be the easiest to maintain". This would depend on your project. I can think of a couple general strategies:
One stylesheet per template
That is, in a way, the simplest suggestion. Probably the easiest to develop, and each page will bring the minimum needed styles.
However, this makes reusing styles pretty impossible. You won't be able to plunk in a <button class="myclass"> into any template without reincluding the styles for .myclass in every sheet you need them in. Also, if you ever want to automate your style sheets (minifying or concatenating them for production, etc) as is common practice, it won't be very possible from here.
One more downside, you might get some unexpected ordering effects. Like if your "widget.css" ends up being added to the DOM after your "article.css" it may override styles in a different way than it would have if it had appeared earlier in the DOM.
All styles on every page
Again, this is nice and simple. Every page has all stylesheets (or maybe just one giant sheet) included. You can link to it once in your outer layout template. It will be easy to automate minification, etc, and there will never be any surprises related to the order stylesheets are added in.
The obvious downside is lots of unused styles brought to each page. But css is pretty "cheap" in terms of size, so this may not be such a bad downside.
Somewhere in between
Include some styles on every page, and make some either page-specific or template-specific. Realistically, this is probably what most apps end up doing.
You can universally include utility styles meant to be reused (ex button.bigred, form.orderform, etc), as well as dependencies like bootstrap or whatever. I'd also advise including any styles you will need on more than half of your pages (ex styles for your navbar).
Other styles intended for one specific page can be added to that page directly via links.
last note
I try to avoid <style> tags in the html for a couple of reasons:
Lots of js libraries dynamically add or remove <style> tags to your DOM, so leaving that space clear for them avoids possible mistakes or overlaps.
They are a good way to add dynamic or user-managed styles to pages from within your templates. Keep styles that don't change in the stylesheets, to avoid possible mistakes or overlaps with yourself :)
I am looking to the wisdom of the crowd for views on best practice for implementing CSS.
Our site was initially built using SASS compilers for CSS. Over time as more functionality has been added, each with specific styles, the CSS files and partials have become large. Loading all CSS for the entire site seems a waste of resources and time, particularly when a large percent is not utilised on any given page. However I am still told that this is more efficient than either inline styles or CSS style blocks within the page.
I am currently considering stripping down everything but core CSS to the SASS CSS file and then creating a series of specific CSS files that are loaded as required.
How have others approached this problem. Is there a consensus on the "best practice" when CSS files become large?
Thanks
D
You can write SASS only for specific parts of your site and load styles for specific pages only. For example you don't have to load styles for product list when you are on product page.
In the meantime you can have global stylesheet for something like menu, footer.
Loading styles inline or in block prevents styles from caching and makes your user download it each time they open website.
This is the perfect opportunity to clean up your styles and start fresh. I would reccomend you create layout.scss for styles used in all pages, and component_X.scss for specific component styles.
We can write CSS as the following types:
Inline CSS
Embedded CSS
External CSS
I would like to know pros and cons of each.
It's all about where in the pipeline you need the CSS as I see it.
1. inline css
Pros: Great for quick fixes/prototyping and simple tests without having to swap back and forth between the .css document and the actual HTML file.
Pros: Many email clients do NOT allow the use of external .css referencing because of possible spam/abuse. Embedding might help.
Cons: Fills up HTML space/takes bandwidth, not resuable accross pages - not even IFRAMES.
2. embedded css
Pros: Same as above regarding prototype, but easier to cut out of the final prototype and put into an external file when templates are done.
Cons: Some email clients do not allow styles in the [head] as the head-tags are removed by most webmail clients.
3. external css
Pros: Easy to maintain and reuse across websites with more than 1 page.
Pros: Cacheable = less bandwidth = faster page rendering after second page load
Pros: External files including .css can be hosted on CDN's and thereby making less requests the the firewall/webserver hosting the HTML pages (if on different hosts).
Pros: Compilable, you could automatically remove all of the unused space from the final build, just as jQuery has a developer version and a compressed version = faster download = faster user experience + less bandwidth use = faster internet! (we like!!!)
Cons: Normally removed from HTML mails = messy HTML layout.
Cons: Makes an extra HTTP request per file = more resources used in the Firewalls/routers.
I hope you could use some of this?
I'm going to submit the opinion that external style sheets are the only way to go.
inline CSS mixes content with presentation and leads to an awful mess.
embedded CSS gets loaded with every page request, changes cannot be shared across pages, and the content cannot be cached.
I have nothing against either method per se, but if planning a new site or application, you should plan for external style sheets.
Inline
Quick, but very dirty
This is (sadly) also the only really sane option for HTML formatted email as other forms often get discarded by various email clients.
Embedded
Doesn't require an extra HTTP request, but doesn't have the benefits of:
Linked
Can be cached, reused between pages, more easily tested with validators.
You want external css. It's the easiest to maintain, external css also simplifies caching. Embedded means that each separate html file will need to have it's own css, meaning bigger file size and lots of headaches when changing the css. Inline css is even harder to maintain.
External css is the way to go.
Where to start!!??
Say you had a site with 3 pages...
You could get away with Inline CSS (i.e. CSS on the page itself, within tags).
If you had a 100 page website...
You wouldn't want to change the CSS on each page individually (or would you?!)...
So including an external CSS sheet would be the nicer way to go.
Inline CSS is generally bad. It's much easier to modify the style of a page when all the styles are located in one central location, which inline CSS doesn't offer. It's easy for quickly prototyping styles, but shouldn't be used in production, especailly since it often leads to duplicating styles.
Embedded CSS centralizes the styles for the page, but it doesn't allow you to share styles across pages without copying the text of the embedded style and pasting it in each unique page on your site.
External CSS is the way to go, it has all of the advantages of embedded CSS but it allows you to share styles accross multiple pages.
Use external CSS when:
you have a lot of css code that will make your file messy if you put it all inline
you want to maintain a standard
look-and-feel across multiple pages
External CSS makes it a lot easier to manage your CSS and is the accepted way of implementing styles.
If the styles are only needed for one file, and you don't foresee that ever changing to apply to other pages, you can put your css at the top of the file (embedded?).
You should generally only use inline CSS if:
It's a one-time formatting for a specific tag
You want to override the default css (set externally or at the top of the file) for a specific tag
To everyone in the here and now, reading after 2015, with projects like Polymer, Browserify, Webpack, Babel, and many other important participants that I'm probably missing, we have been ushered into a new era of writing HTML applications, with regards to how we modularize large applications, distribute changes and compose related presentation, markup and behavior into self-contained units. Let's not even get started with service workers.
So before anyone forms an opinion on what is and isn't feasible, I would recommend that they investigate the current web ecosystem in their time to see if some issues related to maintainability have been gracefully solved.
Pros:
Allows you to control the layout of the entire site with one file.
Changes affect all documents at the same time.
Can eliminate redundant in-line styling (Font, Bold, Color, Images)
Provide multiple views of the same content for different types of users.
Cons:
Older browsers may not be able to understand CSS.
CSS is not supported by every browser equally.
In this case, the pros far outweigh the cons. In fact, if the site is designed in a specific way, older browsers will display the content much better (on average) than if the site were managed with tables.
If you are using a server side language, why not embed CSS and use conditional programming to display it as necessary? For example, say you're using PHP w/ Wordpress and you want some homepage specific CSS; you could use the is_home() function to show your CSS in the head of the document for that page only. Personally, I have my own template system that works like so:
inc.header.php = all the header stuff, and where page specific CSS would go I put:
if(isset($CSS)) echo $CSS;
Then, in a specific page template (say about.php), I would use a heredoc variable for the page specific CSS, above the line which includes the header:
Contents of about.php:
<?php
$CSS = <<< CSS
.about-us-photo-box{
/* CSS code */
}
.about-us-something-else{
/* more CSS code */
}
CSS;
include "inc.header.php"; // this file includes if(isset($CSS)) echo $CSS; where page-specific CSS would go ...
<body>
<!-- about us html -->
include "inc.footer.php";
?>
Is there something I'm missing that makes this approach inferior?
Pros:
1) I can still cache the page using standard caching techniques (is there a caching method that takes advantage of a CSS only external file??).
2) I can use php for special case conditional formatting in specific class declarations if absolutely necessary (PHP doesn't work in a CSS file, unless I'm missing some server directive I could set).
3) All my page specific CSS is extremely well organized in the actual PHP file in which it's being used.
4) It cuts down on HTTP requests to external files.
5) It cuts down on server requests to external files.
Cons:
1) My IDE program (Komodo IDE) can't follow the Heredoc formatting to properly highlight the CSS, which makes it slightly harder to debug syntax errors in the CSS.
2) I really can't see any other con, please enlighten me!
What are some pros/cons in using CSS as part of a theme instead of manually supplying <link> tag in the <head> section of a web page?
In ASP.NET, using a theme makes it easier to integrate your CSS styles with the Localization, Accessibility, and Navigation features of that development platform.
Using your own manual CSS file (referenced from the HTML with a <style> or <link> tag) means that you have to maintain the file yourself, potentially including any browser-specific CSS code. However, going this route will probably afford you a higher degree of portability if, for instance, you decided to switch to another platform (eg. LAMP).
I know that there are questions regarding this same topic, but for HTML. What are some good conventions in regards to using external stylesheets in a Flex app.? How would you break up the stylesheets (names of stylesheets and what they include)?
Flex compiles the external CSS file when you publish your project.
There is a way to load CSS at runtime using Flex; it can be done by compiling CSS files into SWF files and load them at runtime using StyleManager.loadStyleDeclarations.
See the LiveDocs on Stylesheets at Run Time for more info.
Some conventions we use in organizing stylesheets:
Have one main.css stylesheet that holds all of the data for skinning the base application.
Have one fonts.css stylesheet to store all of the fonts in the main app, because these can get quite messy.
The main.css stylesheet is included in the main swf via the <mx:Style source="main.css"/> tag. We load our app with as little as possible, and once everything is loaded, if we need to immediately show some text (sometimes we just have a video playing if it's an advertising site), we fade/tween in the main elements and load the fonts.css via StyleManager.loadStyleDeclarations at runtime.
If we have an admin panel, we have an admin.css stylesheet which we load at runtime because the main app doesn't need it.
We don't need to divide up the CSS anymore than that because we usually create a whole set of skins in a Theme, so the stylesheet is just applying those skins to components and is pretty lean (using Flex 4). I tend not do divide stylesheets into anything smaller (like "pages.css", "comments.css", "popups.css", or even "controls.css", etc.) because it would be overkill and too much to manage for little in return. That's common with HTML, but that's because HTML requires CSS for nice presentation; Flex could do without CSS entirely.
When developing, one of us usually develops most of the skin right away (having a default wireframe setup, like those found on ScaleNine as they do the photoshop/flash/after-effects. There's no way to not have to recompile the css swf if you make changes. But if it is loaded at runtime, you only have to recompile the css file and not the main swf, which is useful but not really useful during hardcore skin development.
I tried keeping the main stylesheet separate during development (in a custom Theme), and it made development a LOT harder, because I had to recompile the css separately every time I made a change and sometimes I had to recompile the main app too, and there were strange and hard-to-track-down bugs, etc. Then I was compiling two different apps. So I recommend keeping the main css file part of the main app.
If you wanted runtime css without having to recompile anything, try Ruben's CSS Loader and check out the source. But that would come at a runtime performance cost.
Flex is not something I've dealt with, but I did some research. It looks like the code to call a remote stylesheet is this:
<mx:Style source="com/example/assets/stylesheet.css" />
Flex Quick Start: Building a simple user interface: Styling your components says this:
Note: You should try to limit the
number of style sheets used in an
application, and set the style sheet
only at the top-level document in the
application (the document that
contains the tag). If
you set a style sheet in a child
document, unexpected results can
occur.
The implication of this seems to be that multiple stylesheets are not really possible. It sounds like what you want to do is organize your stylesheets, check out Organizing Your Stylesheets and Architecting CSS for some ideas for approaches. It looks like you have classes and basic tags, but the W3C stylesheet specifications are different from the Flex stylesheet specification.
As a non-Flex developer, Namespaces looks interesting as a way to organize namespaces: How to use the new CSS syntax in Flex 4.