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 Going Further with Attribute Selectors and Pseudo-Classes Substring Matching Attribute Selectors - "Begins With" and "Ends With"

Sean Flanagan
Sean Flanagan
33,235 Points

Background-size

If the width and height of background-size are the same, doesn't it make sense to type:

background-size: 18px;

2 Answers

Steven Parker
Steven Parker
231,198 Points

It does seem like it might make sense, but that's not the way it works.

The first value sets the width, the second value sets the height. If only one value is given, the second is set to "auto". So by default, the height is set so that it preserves the aspect ratio of the image.

So to constrain both the height and width, provide the value twice:

background-size: 18px 18px;
Sean Flanagan
Sean Flanagan
33,235 Points

I understand. Thanks for your help. I've upvoted your reply and given you Best Answer.

Thank you

Sean :-)