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Tristan Johnson
Courses Plus Student 3,022 PointsWhere did #gallery li:nth-child(4n) come from?
It wasn't addressed in any previous videos. What does it even do?
2 Answers
Jason Anello
Courses Plus Student 94,610 PointsHi Tristan,
It was addressed in the previous video at around the 8:15 mark - https://teamtreehouse.com/library/how-to-make-a-website/responsive-web-design-and-testing/build-a-three-column-layout
After setting the width to 28.3333%, Nick shows what the problem is with the captions and how nth-child fixes the problem.
Also, be sure to check out the teacher's notes for that video because it contains an important correction for the nth-child expression and an explanation. It should be 3n + 1 and not 4n
Sean T. Unwin
28,690 Points#gallery li:nth-child(4n) means to select the fourth list item in #gallery.
You can learn about nth-child() from the CSS Selectors course.