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CSS CSS Basics (2014) Basic Selectors Class Selectors

Posted by Liwei Xu
Liwei Xu
3,323 Points

ID selector for multiple pages?

Can an ID selector in css file apply to multiple pages? Say if you have a standard section in your html files of <header id = "top"> for every page of your website, can you use id selector here? Or in this case, a class would be better?

4 Answers

Máté Végh
Máté Végh
25,607 Points
Máté Végh
Máté Végh
25,607 Points

It's perfectly okay to use the same ID on different pages, just make sure you don't use the same ID for different elements inside one page.

Yaroslav Kleshchev
Yaroslav Kleshchev
8,744 Points
Yaroslav Kleshchev
Yaroslav Kleshchev
8,744 Points

Its fine to use them if they are different pages. However on the same page, id should be unique. If you want to label different elements with the same attribute use classes. multiple elements can has the same class.

Mitchell Springer
Mitchell Springer
2,576 Points
Mitchell Springer
Mitchell Springer
2,576 Points

IDs should typically be used once. If it's something that is going to repeat on multiple pages, you should use a class.

Demauri Portis
Demauri Portis
4,809 Points
Demauri Portis
Demauri Portis
4,809 Points

From my knowledge, classes can be repeated throughout html while IDs are used just once.