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CSS CSS Selectors Advanced Selectors :nth Pseudo-Class Challenge

Pascal Klau
Pascal Klau
15,748 Points

I don't get this question. img:nth-child(4), img:nth-child(3n+1) seems wrong even though it displays the images.


/* Write the CSS in the media query below */

@media (min-width: 607px) {
  img { float: left; }
  img:nth-child(4), img:nth-child(3n+1) { clear: both; }
<!DOCTYPE html>
  <meta name="viewport" content="width=device-width, initial-scale=1">
  <link rel="stylesheet" href="page.css">
  <link rel="stylesheet" href="style.css">
    <img src="thumb-forest.jpg" alt="">
    <img src="thumb-resort.jpg" alt="">
    <img src="thumb-trees.jpg" alt="">
    <img src="thumb-falls.jpg" alt="">
    <img src="thumb-view.jpg" alt="">
    <img src="thumb-sunset.jpg" alt="">
    <img src="thumb-lake.jpg" alt="">
    <img src="thumb-beach.jpg" alt="">
    <img src="thumb-bay.jpg" alt="">
    <img src="thumb-peaks.jpg" alt="">
    <img src="thumb-falls.jpg" alt="">
    <img src="thumb-resort.jpg" alt="">

1 Answer

Jennifer Nordell
Jennifer Nordell
Treehouse Teacher

You're pretty close here! You have one img:nth-child that's not needed and the clear is supposed to be left (not both) as indicated by the challenge. The img:nth-child(3n+1) would be correct if we were starting with the first child and taking every third after. However, it states that we start with the fourth child, so that 3n+1 should be changed to 3n+4. The +num is our starting child point. Take a look here:

/* Write the CSS in the media query below */

@media (min-width: 607px) {
  img { 
    float: left; 

  img:nth-child(3n+4) {   /* start at fourth element and apply to every third element after */
    clear: left;   /*  clear left instead of both */

Hope this helps!