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CSS CSS Layout Techniques Float Layout Mobile First Layout

What does ::after {content: " "} mean? Why is content empty?

Title says it all.. What does ::after {content: " "} mean? Why is content empty?

Niclas Valentiner
Niclas Valentiner
8,947 Points

From my understanding content: " " effectively generates a new empty element. The only place I've seen this used is for float clearfix though so I'm not certain.

As for float clearfix itself, I recommend you check this video on the subject: https://teamtreehouse.com/library/css-layout-techniques/float-layout/the-float-clearfix

1 Answer

Chris Shaw
Chris Shaw
26,676 Points

Hi James,

The content property is required on all pseudo elements which are defined using :before and :after. By itself, a pseudo element won't do anything as browsers won't draw the element unless a string as simple as '' is used in the content property.

For example.

/* this will not render */
#element:before {}

/* this will render */
#element:before {
  content: 'hello';
}

In your case I assume you're referring to a clearfix technique which contains floats by adding an element that is very small and invisible to the eye.

Hope that helps.