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CSS

Specificity and psuedoclasses

Hello guys,

I was playing around in the CodePen attached to lesson: http://teamtreehouse.com/library/css-foundations/advanced-selectors/additional-pseudoclasses

The only change I made to my CSS is that I altered the target pseudo-classes' background color to steelblue. It looked like this: :root { background-color: #e0eef5; }

:target { color: white; background-color: steelblue; }

div:not([id="s2"]) { background-color: tomato; }

Why is that when I click the targets, the background-color change only applies to target section 2? I understand that target section 2 accepts the background-color change because it is not specified under div:not([id="s2"]). However, why doesn't the color change to steel blue when I click on target sections 1 and 3? Is it because div:not([id="s2"]) has a greater specificity than :target? If yes, why is this so?

Thank you for your help!

Alex Tasioulis
Alex Tasioulis
4,950 Points

I think the problem here is that :target points to the root of the page (not the :root pseudoclass), whereas div:not points to divs, which are a lot lower down the hierarchy and therefore a lot more specific. If you do div:target instead of just :target, it should override your div:not([id="s2"]).

Thank you Alex. You were really helpful!

1 Answer

Specificity hierarchy Every selector has its place in the specificity hierarchy. There are four distinct categories which define the specificity level of a given selector:

  1. Inline styles (Presence of style in document). An inline style lives within your XHTML document. It is attached directly to the element to be styled. E.g. <h1 style="color: #fff;">
  2. IDs (# of ID selectors) ID is an identifier for your page elements, such as #div.
  3. Classes, attributes and pseudo-classes (# of class selectors). This group includes .classes, [attributes] and pseudo-classes such as :hover, :focus etc.
  4. Elements and pseudo-elements (# of Element (type) selectors). Including for instance :before and :after. If you donโ€™t know what exactly each of these terms stands for, you can take a look at the brief overview of them; in the last section of this article.

From: http://coding.smashingmagazine.com/2007/07/27/css-specificity-things-you-should-know/

Thanks!