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CSS How to Make a Website Responsive Web Design and Testing Build a Three Column Layout

Alexandru Dan Dodu
Alexandru Dan Dodu
2,910 Points
Posted by Alexandru Dan Dodu
Alexandru Dan Dodu
2,910 Points

Shouldn't be :nth-child(3n+1) instead of :nth-child(4n)

I think it should be :nth-child(3n+1) instead of :nth-child(4n)

2 Answers

Jason Anello
Jason Anello
Courses Plus Student 94,610 Points

Hi Alexandru,

You're correct. For the general case of an unknown number of images, it should be 3n + 1

The "Teacher's Notes" below the video has a code correction for this.

SERGIO RODRIGUEZ
SERGIO RODRIGUEZ
17,532 Points
SERGIO RODRIGUEZ
SERGIO RODRIGUEZ
17,532 Points

Hi Alexandru,

You can think that the argument of the nth child selector works like this:

  • "an+b":

  • a = target every "a" elements

  • b = being "b" the first element selected

So an argument of 3n+1 reads: "target every 3 elements being 1 the first element selected". This means that in a list of 10 elements, elements 1, 4, 7 and 10 will be targeted.

On the other hand 4n reads: "target every 4 elements being 0 de first element selected". This means that in a list of 10 elements, elements 0, 4 and 8 will be targeted.

As you can see, both arguments lead to different results, which means they are not the same. Keep in mind that 3n+3 will indeed lead to the same results as 3n.

Best regards,

Sergio