Welcome to the Treehouse Community

The Treehouse Community is a meeting place for developers, designers, and programmers of all backgrounds and skill levels to get support. Collaborate here on code errors or bugs that you need feedback on, or asking for an extra set of eyes on your latest project. Join thousands of Treehouse students and alumni in the community today. (Note: Only Treehouse students can comment or ask questions, but non-students are welcome to browse our conversations.)

Looking to learn something new?

Treehouse offers a seven day free trial for new students. Get access to thousands of hours of content and a supportive community. Start your free trial today.

HTML How to Make a Website Styling Web Pages and Navigation Make a CSS Image Gallery

Beki Sonin
Beki Sonin
1,705 Points

What does it mean when i'm asked "Add CSS that will allow all images to fill their parent element."?

I'm taking a code challenge and it's asking my that question, and I dont understand the wording. When I tried to put my CSS on workspace in the code challenge to get a hint on what im doing wrong, it just lets me know that I didnt put the max width on my imagines, and I dont understand how those two things are related.

a {
  text-decoration: none;

#wrapper {
  max-width: 940px;
  margin: 0 auto;
  padding: 0 5%;

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

h1, h2 {
  color: #fff;

nav a, nav a:visited {
  color: #fff;

nav a.selected, nav a:hover {
  color: #32673f;

h1 {
  font-family: 'Arvo', sans-serif;
  margin: 15px 0;
  font-size: 1.75em;
  font-weight: normal;
  line-height: 0.8em;

1 Answer

Kirkland Harrell
Kirkland Harrell
4,444 Points

The hint is letting you know it wants you to set the max-width of all images.

Setting it to 100% will allow it to fill its parent element.

img {
 max-width: 100%;