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Edwin Goddard
8,988 PointsIs the nth-child right
should it not be 3n+1 so that it's the first one on every row of 3?
4n will be 4, 8, 12
we want 4, 7, 10
3 Answers
Cherie Burgett
8,711 PointsIn the teachers notes under this video
"A more robust solution is to use the selector :nth-child(3n + 1) instead. This will select every 3rd item plus 1. In other words, this will select the 4th item, 7th item, 10th item, and so on.
Edwin Goddard
8,988 PointsThanks for that. I hadn't even noticed.
Thomas Gallagher
3,900 PointsActually, (3n+1) will select the 1st, 4th, 7th item and so on.
n starts at 0 so 3n+1 is equivalent to 3(0)+1, 3(1)+1, and so on. If you want to select every third element starting at the fourth element the proper expression would be (3n+4).
Jason Anello
Courses Plus Student 94,610 PointsHi Thomas,
Yes, that's correct. The notes don't specify that the first item would be selected too.
It doesn't hurt to clear the first item although it isn't strictly necessary. I would recommend doing it for the sake of consistency.
Edwin Goddard
8,988 PointsThanks for your help.
Jason Anello
Courses Plus Student 94,610 PointsJason Anello
Courses Plus Student 94,610 PointsHi Edwin,
This is also a problem for the 2 column layout.
You can find more info about this problem in this post: https://teamtreehouse.com/forum/3-column-layout-nth-clear-not-working