It is not working

Nathan;

As Aurelian mentioned it is a generally accepted practice on the forum to reference the challenge and task as well as to post the code you are using so that folks can help with the code that should be used. Sometimes there are subtle but highly important differences between the two that can change the code overall and still be valid code, or create a syntax error that isn't valid. Either way most of the challenge engines on Treehouse are looking for something specific so the subtleties can make a big difference.

In looking at your user profile, it looks like you are back at Treehouse after a bit of a break, so Welcome Back!

This particular set of challenges is, in my opinion, very important while learning CSS as it focuses on some of the essential skills in CSS, upon which much is built. Without having a firm grasp of these skills, future CSS courses will be difficult to follow.

So, while it is not recommended that folks simply regurgitate code for challenges, I am feeling a bit generous, so as long as you promise that if you don't understand something you go back and review the video(s) on CSS as, like I said, these are very important CSS ideas.

/**********************************
/ COURSE: How to Make a Wesite
/ Module: CSS: Cascading Style Sheets
/ Challenge: Style the Basic Elements
/ Tasks: 1-3
/*********************************/

/* Task 1:
* Remove the underlines from all the links on the page.
*/

a {
  text-decoration: none;
}

/* Task 2:
* Select the ID wrapper, set it to a max width of 940 pixels, 
* and then center it on the page using the margin property.
*/

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

/* Task 3:
* Select the element with the ID logo and center the text using text-align.
*/

#logo {
  text-align: center;
}

Please post back if a) it helps, b) it doesn't make sense, or c) you have other questions or comments.

Happy coding,

Ken