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Amber Hoddinott
Amber Hoddinott
6,494 Points

Would someone please be able to explain to me how this css works, and why it underlines? :)

Hi i have found the answer to css styling i have been trying to do, but i dont understand how it works, i was hoping someone might be able to explain to me why this css underlines? Maybe i have missed something but i thought :after was used when something has had an action happen to it, for example if a link is clicked on you can change the color using the :after pseudo css. Therefore im confused to why this underlines?

Thank you in advance.


3 Answers

Hi Amber,

    content: "";
    position: absolute;
    width: 50%;
    height: 1px;
    bottom: 0;
    left: 25%;
    border-bottom: 1px solid red;

This code isn't the best example of the :before pseudo classes as you've already got another styling controlling the position of the element; position: absolute. So, you could use the :after class here and it would still show the same way.

:after literally just places something after the given element (here, the h1 tag), and :before would just place something before.

It's got nothing to do with interactive states, such as :hover, :focus, :active, and so on. It's just about positioning an object on the page.

A good example is if you had a bulleted list, but you wanted to use custom images for the bullets. You could write your list, and then write something like:

li:before {
    content: "your chosen bullet image";
    padding-right: 10px;

to place your custom bullet before each list element, with a bit of spacing in between.

Hope that helps,


Hi Amber!

I'm not great at CSS, I'm afraid. However, the pseudo elements ::before and ::after, I thought, we positioning rules such that you could do something like:

h1::before {
  content: "dog.jpg";

which would position an image before the h1 element. Your question mentions visited links etc. I think that's a different pseudo element, :visited and others like :hover.

Again, I'm not great with CSS but those are my thoughts.


Amber Hoddinott
Amber Hoddinott
6,494 Points

Thanks Ede, :) yes this helped alot... we are all learning constantly!! I will remember this for my next project as i would like to use custom bullet points in that! Thank you AMBER