CSS Pseudo Element
I came across the ::after element when constructing a responsive design.
I have tried to change the CSS file and the HTML template to see exactly what is happening here - in all cases (so far) all that I managed to do is to break the page.
The ::after pseudo class is used to add some (cosmetic) content after the content. In my case I am assuming that I am clearing and floating any content after the div class="row".
In some respects I should not use something that I don't understand or worse can't explain. However, it has been working for me for a while. The link to css-tricks.com gives some sort of insight into this. The comment:
You want the generated content to come before the element content, positionally.
Seems to be what is happening and the values for content: ""; (the code in the clearfix)
There is also reference to clearfix which I was experimenting with floating images.
Update: I now understand this technique. See my page on what happens when you don't use a clearfix
first-letter example selector.class::first-letter - from the W3C website
This is an introduction.
This is a paragraph with some text, the first letter of which is coloured and a different font size. The second line in a paragraph should not be coloured and be the same font
A paragraph only has one first letter. As such you can add the colour and text as in this example you can change the first line using ::first-line. This is the second sentence. This is an exampe of multiple classes.
The ::after example - from my rwd.css file
I am still not sure what is going on here.
The CSS is:
.row::after {
content: "";
clear: both;
display: block;
}
and HTML is: <div class="row">
The container <div class="row"> is placed around two other <div> classes:
<div class="rcontent-menu menu"> and
<div class="rcontent-main">
The class "row" is a pseudo-class and an example of clearfix. Without this the footer and trepeat containers don't position below the main container.
Links
- My RWD css file - where I use the ::after technique in my responsive design
- W3C Resources
- Floating Images and wrapping text - CSS - I use clearfix on my page on Heraldry
- Responsive Image Grid
- Clearfix
External Sources
- Pseudo-Elements 🔗
- Pseudo-Classes 🔗
- ::before / ::after 🔗 - css-tricks.com
- Multiple Classes 🔗 - W3C
css Pseudo Element - November 2019