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CSS CSS Foundations Advanced Selectors Pseudo-Elements: ::before and ::after

What are some possible uses for the ::before and ::after pseudo-elements?

Why would I do that instead of just creating separate elements in the HTML?

Sorry if it's a silly question!

4 Answers

Here's some more use cases for those pseudo elements:

You'll find that most, if not all of the time, they're used for stylistic reasons. The reason you don't want to add these extra elements in your html is because you're littering your markup with non semantic elements for the sole purpose of using them as css hooks so that you can simply attach more styles.

This doesn't keep your content and presentation layers separate.

Richard Duncan
Richard Duncan
5,568 Points

If you look on this page top left where there is an arrow pointing to the nav menu on the left and the word Forum which darkens when you hover over the link this is a good example of where pseudo classes may be used.

Say you are using h4 elements to highlight key links for users of your website. You could as you say create additional elements in the mark up of your HTML, but this can get messy and what if you forget to add the element somewhere or you want flexibility in future to say update the arrow to a star. You could use the :before pseudo to apply an arrow onto the page as follows: -

    content: "&#8592 ";

I use :after and :before in different cases. In a downloads page i use it to apply the extensions to the links: http://jsfiddle.net/nxYQS/ . Or if you want to apply quotes before and after a quote: http://jsfiddle.net/6hnQM/ . It is handy too when you need more than one border on an element. Checkout this: http://code.tutsplus.com/tutorials/quick-tip-multiple-borders-with-simple-css--net-12471

Thank you all for the responses, each valuable in their own right!