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CSS CSS Selectors Advanced Selectors :nth Pseudo-Class Challenge

Posted by Chris Paraoan
Chris Paraoan
4,481 Points

Confused on this challenge task. Question 2 of 3

We want three floated images per row. In the media query, create a pseudo-class selector that targets the fourth img child element first, then every third img that follows. Then, add a clear property that clears the left float.

style.css 
/* Write the CSS in the media query below */

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

}
index.html 
<!DOCTYPE html>
<html>
<head>
    <title>Selectors</title>
  <meta name="viewport" content="width=device-width, initial-scale=1">
  <link rel="stylesheet" href="page.css">
  <link rel="stylesheet" href="style.css">
</head>
<body>
    <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="">
</body>
</html>

9 Answers

Donald Wilson
Donald Wilson
5,418 Points
Donald Wilson
Donald Wilson
5,418 Points

Here is the code I used to get the correct answer for the question on Challenge Task 2 of 3

"We want three floated images per row. In the media query, create a pseudo-class selector that targets the fourth img child element first, then every third img that follows. Then, add a clear property that clears the left float."

@media (min-width: 607px) {
  img {
    float: left;
  }
  img:nth-child(3n+4) {
    clear: left;
  }
}
derekverrilli
derekverrilli
8,841 Points
derekverrilli
derekverrilli
8,841 Points

4n + 3 isn't every 7th child. It means start with the 3rd child then select every 4th child after that.

"...targets the fourth img child element first, then every third img that follows"

This would be 3n+4.

Also, for this {clear: float-left;} , it should be {clear: left;}

Chris Paraoan
Chris Paraoan
4,481 Points

Thanks Derek!!

ellie adam
ellie adam
26,377 Points
ellie adam
ellie adam
26,377 Points

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

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

Richard Targett
Richard Targett
4,960 Points
Richard Targett
Richard Targett
4,960 Points

If only treehouse offered hints -_-

very helpful. But if your not 100% sure of this logic whats the best way to let this stuff sink in? [Practice] Im guessing?

John Magee
PLUS
John Magee
Courses Plus Student 9,058 Points
John Magee
John Magee
Courses Plus Student 9,058 Points

Chris

There's two errors in your error.

  1. 4n already refers to the 4th child - I don't even know if 4n + 3 works but if it does it's referring to every 7th child
  2. clear is a property all in itself, like float, you don't have to re-state float, you just indicate the 'direction' where you want to clear (left, right, both are the standard options)
Chris Paraoan
Chris Paraoan
4,481 Points

John,

Thanks for explaining it in detail, it really helped me out. Thanks again!

Jose A Reynaldo Vazquez
Jose A Reynaldo Vazquez
21,313 Points
Jose A Reynaldo Vazquez
Jose A Reynaldo Vazquez
21,313 Points

This is the correct answer:

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

John Magee
PLUS
John Magee
Courses Plus Student 9,058 Points
John Magee
John Magee
Courses Plus Student 9,058 Points

The video before the quiz goes into this

You need to use nth-child(4n).

Chris Paraoan
Chris Paraoan
4,481 Points

Thanks John for replying... I wrote this img:nth-child(4n + 3) {clear: float-left;} Got an error.