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CSS How to Make a Website Customizing Colors and Fonts Write Hexadecimal Colors

Thomas Weld
Thomas Weld
12,293 Points

Why a.selected vs a:hover ?? Why period vs colon?

wondering why the syntax is different for selected vs hover ?

4 Answers

Jonathan Grieve
MOD
Jonathan Grieve
Treehouse Moderator 91,253 Points

When you use a.selected, what you're doing is selecting an anchor element with a class of selected. . Is that CSS notation for a class.

a:hover on the other hand is what's known as a pseudo selector. It triggers a CSS property change by a user triggered action, in this case, a mouse hover.

When you use a period, that means that you want to select an element with that specific class. E.g.

div.classgoeshere {
    // Code
}

Classes has to be added into the HTML while pseudo-classes can be used without targeting a class/id.

When you use a colon, that means you want to use the pseudo-classes. These are used to refine your selection. E.g.

div:pseudo-class {
    // Code
}

Pseudo classes are really handy when you have a lot of html and don't want to add ids and classes all over the place. You can read more about them here.

Gianni Zamora
Gianni Zamora
9,547 Points

a.selected means that it will apply those style to whicher link or div is clicked and selected. The a:hover is adding css to apply ONLY when you hover over the item. The difference between a period and colon, well I don't really know maybe other than that is how html accepts the syntax.

Thomas Weld
Thomas Weld
12,293 Points

I guess I'm wondering why the syntax would be different for the link states of selected vs. hover ? Here is the example:

nav a.selected, nav a:hover { color:#32673f; }