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CSS

Ceci Kellen
Ceci Kellen
4,749 Points
Posted by Ceci Kellen
Ceci Kellen
4,749 Points

: vs ::

In the example in this video, the CSS code used to generate clearfix is:

.group:after { content: ""; display: table; clear: both; }

In additional resources, https://teamtreehouse.com/library/css-selectors/advanced-selectors/pseudoelements-before-and-after, the CSS code used to generate clearfix is:

.jpg::before { content: ""; font-size: 0.75em; }

What's the difference between using a single : vs a double :: ?

1 Answer

Iain Simmons
MOD
Iain Simmons
Treehouse Moderator 32,305 Points
Iain Simmons
Iain Simmons
Treehouse Moderator 32,305 Points

:: (double colons) are used for pseudo-elements (think, anything where you use the content property), while : (single colon) is used for pseudo-selectors (selecting an existing element based on certain criteria, like :hover if the user's mouse is hovering over it, or :first-child if it's the first child element of a parent.

Using single colons for pseudo-elements is still supported in all browsers for backwards compatibility, so everything will still work if you just use single and forget which is which.