"Interactive Web Pages with JavaScript" was retired on March 17, 2017. You are now viewing the recommended replacement.

Heads up! To view this whole video, sign in with your Courses account or enroll in your free 7-day trial. Sign In Enroll

CSS Basics

Well done!

You have completed CSS Basics!

Sign up for Treehouse Back to Library

Validation

3:23 with Anwar Montasir

As we wrap up this course, I’ll leave you with one final important resource. The W3C CSS Validator is great for helping you spot errors in your CSS.

Further reading

Related Discussions

Have questions about this video? Start a discussion with the community and Treehouse staff.

Sign up

    Related Discussions

    Have questions about this video? Start a discussion with the community and Treehouse staff.

    Sign up

    Congratulations, you've made it to the end of CSS basics. 0:00
    You've learned all sorts of CSS selectors, worked with a variety of 0:05
    measurements, and checked out how the CSS cascade settles conflicts. 0:09
    While there's plenty more to learn about controlling your layout 0:15
    with CSS, be sure to refer back to the lessons and resources you 0:18
    learned here often and keep practicing. 0:22
    As we wrap up this course, I'll leave you with one final important resource. 0:27
    The W3C CSS validator is great for helping you spot errors in your CSS. 0:32
    The validator offers three ways to validate your CSS file. 0:40
    If it's hosted on a web server already, you can paste in the URL. 0:45
    Or if it's local to your machine, you can choose the by file upload feature. 0:51
    Since I'm using a workspace, I'm just going to copy my code and 0:57
    paste where it says by direct input. And it looks like I have no errors. 1:03
    But what if I do have errors? 1:10
    I'm going to try making a few on purpose, since understanding 1:13
    error messaging is a critical part of being a developer. 1:17
    I'll remove the closed curly brace after my header selector, 1:22
    remove the colon here in my footer declaration, and delete 1:27
    the closed parenthesis in my rgba declaration within the 1:32
    a :focus selector. And let's validate again. 1:38
    Sometimes validation errors look pretty intimidating, don't they? 1:45
    The only clue I have here really is that the error is made on 1:50
    my header selector. And without that closed curly brace, 1:54
    the validator is getting confused about the rest of my CSS 1:58
    and trying to read it as one giant CSS rule. 2:03
    So let's restore that closed brace and try validating again. 2:07
    Okay, these errors are much more straightforward to fix. 2:17
    Not only do we see the selector names, footer and a:focus, but 2:21
    we see the specific line numbers where corrections need to be made. 2:26
    So I'll go ahead and make the fixes. 2:33
    And we're congratulated again. No errors found. 2:47
    So keep that validator handy, along with other resources 2:52
    we've covered here. You'll naturally start memorizing parts of CSS code 2:56
    syntax the more you practice, but being a great developer 3:00
    isn't really about memorization. It's important to know what 3:05
    resources can help you get unstuck, about knowing how to spot and 3:09
    correct errors, and most importantly, about believing you can do it. 3:14
    And by completing this course, you've already come a long way. 3:19

    You need to sign up for Treehouse in order to download course files.

    Sign up

      You need to sign up for Treehouse in order to set up Workspace

      Sign up