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CSS How to Make a Website Styling Web Pages and Navigation Build Navigation with Unordered Lists

Yariv Steinberg
Yariv Steinberg
1,788 Points
Posted by Yariv Steinberg
Yariv Steinberg
1,788 Points

What's the difference between: gallery { x:y; } and #gallery { x:y; } ?

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2 Answers

Ryan Field
PLUS
Ryan Field
Courses Plus Student 21,242 Points
Ryan Field
Ryan Field
Courses Plus Student 21,242 Points

Hi, Yariv. In CSS, a hash (#) indicates that you want to style an element with a particular ID. Similarly, a period (.) indicates a class, while a colon (:) represents pseudo elements and selectors. Items without any prefixing punctuation mean that you want to target elements themselves, such as div or p. These must be actual elements used for HTML markup, and since there is no gallery element, you cannot use simply gallery in your CSS; you must use either .gallery or #gallery.

Jason Anello
PLUS
Jason Anello
Courses Plus Student 94,610 Points
Jason Anello
Jason Anello
Courses Plus Student 94,610 Points

Hi Yariv,

Your first selector example would be invalid because it would be looking for an html element named "gallery" and there is no element with that name.

It's looking for something like this:

<gallery></gallery>  <!-- This is invalid html -->

In your second example the selector is looking for an element with an id attribute of "gallery"

An example from this project:

<ul id="gallery">
</ul>

Since the ul has an id attribute of "gallery" the selector #gallery will match that element.

id selectors are always prefixed with # followed by the id and class selectors are always prefixed with . followed by the class name. Element selectors are just the name like p, or h1