Challenge http://www.freecodecamp.com/challenges/waypoint-give-a-background-color-to-a-div-element has an issue. Please describe how to reproduce it, and include links to screenshots if possible.
Created a class called .gray-background as instructed, gave this class to div element. Doesn't work when I click the Run Code button but works in the preview.

@jasellis thanks for posting this issue!
I've just passed the tests with your code both in FF and Chrome (in Incognito mode).
Please review the Guidelines for Contributing, thank you!.
Works for me too. Seems to be an issue on your end.
Please check your ChromeDevTools console and report back with any errors on there.
Okay turns out it was an extension called Privacy Badger. I disabled it for FCC and everything seems to be working now. :+1:
@jasellis you can now close this issue if you solved your problem, thanks.
Please review the Guidelines for Contributing, thank you!.
Doesn't work


Invalid property value.
Ubuntu 15.10
Google Chrome Version 46.0.2490.80 (64-bit)
Workaround:
<div class="gray-background" style="background-color: gray">
Thank you, it worked - first i added the above example and then added this.
I had the same issue in chrome, the workaround did the trick!
turns out i had left a space between the SILVER- BACKGROUND
Jeez i am a newb
Big Tip!!!!! disable ad blocker or pause it. everything working right way!!!
Most helpful comment
Invalid property value.
Ubuntu 15.10
Google Chrome Version 46.0.2490.80 (64-bit)
Workaround: