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CSS CSS Basics (2014) Basic Selectors Class Selectors

Micole Noddle
Micole Noddle
5,797 Points
Posted by Micole Noddle
Micole Noddle
5,797 Points

Why use both an id and a class for the header? Don't we need a div for an id? I find that code to be very confusing...

I've never seen it written this way. Isn't there a cleaner way to do it?

Micole Noddle
Micole Noddle
5,797 Points
Micole Noddle
Micole Noddle
5,797 Points

Oh, sorry, here's the code from Guil's video:

<header id="top" class="main-header">

3 Answers

Wendy Peralta
Wendy Peralta
11,203 Points
Wendy Peralta
Wendy Peralta
11,203 Points

Hey! I believe the reason why he kept the id="top" in the header is because remember at the bottom of the page, we have a link that says "Back to top >>" which when clicked, takes you back to the top of the page. The way to achieve this is by adding the id "#top" to the href attribute in the anchor tag: <a href="#top">Back to top »</a>

Since we want to style the header as well, we can go ahead and give it a class, even though it already has an id. And like David Tonge said, IDs are not exclusively for divs. You can use IDs in any element.

Hope this helps! :)

David Tonge
PLUS
David Tonge
Courses Plus Student 45,640 Points
David Tonge
David Tonge
Courses Plus Student 45,640 Points 
You don't need a div to use an ID. You can actually add an ID to any element.

ID's are unique
Each element can have only *one* ID
Each page can have only one element with that ID

Classes are NOT unique

You can use the same class on multiple elements.
You can use multiple classes on the same element.

You can have both. IDs are good as hooks for Javascript.
ANDREA HEMPHILL
ANDREA HEMPHILL
14,484 Points
ANDREA HEMPHILL
ANDREA HEMPHILL
14,484 Points

I think that using both allows you to make specific changes to the header by using the ID, and then shared changes by using the class. For example, we may want the top header section to always stay blue, so we would use an ID, but we may want the text to match the paragraphs in the body so we could use the class.