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 How to Make a Website Responsive Web Design and Testing Refactor the Layout

inside the query,clear the left of every 4th list item in the galley

-inside the query,clear the left of every 4th list item in the galley

css/main.css
a {
  text-decoration: none;
}

#wrapper {
  max-width: 940px;
  margin: 0 auto;
}

#logo {
  text-align: center;
  margin: 0;
}

h1, h2 {
  color: #fff;
}

nav a {
  color: #fff;
}

nav a:hover {
  color: #32673f;
}

h1 {
  font-family: Changa One, sans-serif;
  font-size: 1.75em;
  font-weight: normal;
}

img {
  max-width: 100%;
}

#gallery {
  margin: 0;
  padding: 0;
  list-style: none;
}

#gallery li {
  float: left;
  width: 45%;
  margin: 2.5%;
  background-color: #f5f5f5;
  color: #bdc3c7;
}

nav ul {
  list-style: none;
  margin: 0 10px;
  padding: 0;
}

nav li {
  display: inline-block;
}

nav a {
  font-weight: 800;
  padding: 15px 10px;
}

.profile-photo {
  display: block;
  margin: 0 auto 30px;
      max-width: 150px;
  border-radius: 100%;
}

.contact-info {
  list-style: none;
  padding: 0;
  margin: 0;
  font-size: 0.9em;
}

.contact-info a {
  display: block;
  min-height: 20px;
  background-repeat: no-repeat;
  background-size: 20px 20px;
  padding: 0 0 0 30px;
  margin: 0 0 10px;
}

@media screen and (min-width: 480px) {
  #gallery  li { width: 28.3333%; }
  #gallery li nth-child(4th){clear: left;}
  }

1 Answer

Zoltán Holik
Zoltán Holik
3,401 Points

The formula is :nth-child(an+b), where "a" is a number, "n" is a counter(starts at 0), and "b" is an offset.

#gallery li:nth-child(4n){
  clear:both;
}

It means:

  • (4 x 0) = 0 = no match
  • (4 x 1) = 4 = 4th Element
  • (4 x 2) = 8 = 8th Element
  • (4 x 3) = 12 = 12th Element