Welcome to the Treehouse Community

Want to collaborate on code errors? Have bugs you need feedback on? Looking for an extra set of eyes on your latest project? Get support with fellow developers, designers, and programmers of all backgrounds and skill levels here with the Treehouse Community! While you're at it, check out some resources Treehouse students have shared here.

Looking to learn something new?

Treehouse offers a seven day free trial for new students. Get access to thousands of hours of content and join thousands of Treehouse students and alumni in the community today.

Start your free trial

CSS CSS Selectors Advanced Selectors :nth Pseudo-Class Challenge

davide totaro
davide totaro
5,559 Points

We want three floated images per row. In the media query, create a pseudo-class selector that targets the fourth img chi

i don 't figure out the problem!

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

@media (min-width: 607px) {

  img :nth-child(3n+1){


<!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="">

6 Answers

Clinton Johnson
Clinton Johnson
28,714 Points

img:nth-child(3n+4) { clear: left; }

3×0 + 1 = 3 and 3×1 + 1 = 4


3×0 + 4 = 4 and 3×1 + 4 = 7

Hey Davide,

Why don't you wrap divs around the images and then make those divs width: 33%; This will only allow 3 images on one row at a time.

then you can use media queries to change the amount of images you can have on a line the skinnier your browser gets.



<div class="img-container"> <img src="thumb-beach.jpg" alt=""> </div>


.img-container { width: 33.333%; }

@media only screen and (max-width: 780px) {

.img-container {
        width: 50%;


@media only screen and (max-width: 480px) {

.img-container {
        width: 100%;


You can also set your image widths inside the .img-container as well to give even more flexibility.

Hope this helps!

18,793 Points

Can anyone help me on this? I can't figure out what's wrong with my coding:

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

img:nth-child (3n+4 ) { clear: left; } }

Kern Tallett
Kern Tallett
10,012 Points

Lucy in the off chance you are still stuck, it is because you had a space between nth-child and the brackets. It should be img:nth-child(3n+4)

img :nth-child(3n+1){ clear:left;

benoit koch
benoit koch
3,875 Points

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

img:nth-child(3n+4) { clear: left; } }