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CSS CSS Basics (2014) Getting Started with CSS CSS Resources

Posted by Bridget Word
Bridget Word
3,237 Points

Browser support?

What is browser support? Also what is the site "can I use.com" for?

3 Answers

Ben Reynolds
Ben Reynolds
35,170 Points
Ben Reynolds
Ben Reynolds
35,170 Points

When the developers who maintain web technologies such as javascript, css, etc add new features, the next step is for browser developers to update their browsers to understand those new language features. Since every browser is maintained by a different organization, some browsers will be updated before others. Even browsers from the same developer but for different platforms might have differences, such as Firefox desktop vs mobile.

This is why you sometimes need to add multiple css rules for the same thing (one version for webkit, once for mozilla, etc) but it's not limited to just css. One thing you'll pick up on quick as you test code is how stubborn some browsers can be, particularly internet explorer and edge. I still have an old HTML5 book with a whole section called "Dealing with Internet Explorer."

That's why caniuse was made. It lets you look up a feature and see which browsers (and which versions of them) support it before you spend a bunch of time writing code that doesn't work.

Kieran Barker
Kieran Barker
15,028 Points
Kieran Barker
Kieran Barker
15,028 Points

'Dealing with Internet Explorer', hahaha. I love it.

Kieran Barker
Kieran Barker
15,028 Points
Kieran Barker
Kieran Barker
15,028 Points

Hey Bridget, not all browsers support all features. Can I Use is a website that shows you which features are supported by which browsers :)

Bridget Word
Bridget Word
3,237 Points

So how would I know which browser to write code for? I hope that makes sense.

Ben Reynolds
Ben Reynolds
35,170 Points
Ben Reynolds
Ben Reynolds
35,170 Points

There are a lot of them out there today, but realistically you should at least shoot for Chrome, Safari, Firefox and Edge at a minimum (don't forget to test your site on mobile too). Thankfully this doesn't mean you're going to have to write everything over and over. Most of the common css rules you'll write are pretty consistent across browsers and don't need any trickery, and there are tools to help when they do.

Normalizers, frameworks, preprocessors, all of that stuff is built around getting people closer to a code-once-deploy-anywhere workflow. None of them are perfect but they do make things a lot easier.

I wouldn't stress about that yet though. It looks like you're doing the intro to css course. At this stage, focus on writing good clean plain vanilla css. If you get really comfortable with that, learning that other stuff when you get to it will be pretty straightforward.

In the meantime, I'd recommend going to your favorite site, hit that F12 key and start messing with the css and see what it does. Better yet, pull up the same page side by side different browsers and see if you can spot differences. Since you're essentially just looking at a snapshot of the page when it loads (mostly) you can preview any css changes you want with the dev tools and just refresh the page to reset it.