Java script error message

There is a red ! in the java script panel of code pen. When I click on the down arrow it say label error {a} on {b} statement.
All I have in that panel is the address to running tests.
https://cdn.freecodecamp.org/testable-projects-fcc/v1/bundle.js
https://codepen.io/martin21/pen/PoZqbdQ

please share the link to your pen

https://codepen.io/martin21/pen/PoZqbdQ

ok, the issue is that a link like that has no meaning in javascript, and it’s just a syntax error, but you can take that link and put it in the pen settings for JS

Okay, thanks for that. That was a solution to the “how do I test” question.
I tested to make sure it still passed and it saying the nav-bar is not at the top. Any suggestions about that, or where I should look.
Thanks

your project for me passes all the tests, what do you see written below the failed user story?

Yes it passed a couple of days ago and I was just making some tweaks, checking for errors and the one about the java script error, which has gone, thanks.
Then I ran the test and it complained that the nav-bar was not at the top in view port with this detail:
#header or one of its children should be at the top of the viewport even after scrolling : expected 272.484375 to be close to 0 +/- 15
AssertionError: #header or one of its children should be at the top of the viewport even after scrolling : expected 272.484375 to be close to 0 +/- 15
at Proxy.T (https://cdn.freecodecamp.org/testable-projects-fcc/v1/bundle.js:549:12413)
https://codepen.io/martin21/pen/PoZqbdQ

There are no relative positions. I have make all head elements fixed position and 0px height. I think I have distorted stuff just to solve this test result.

Thanks for looking.
Martin

you have a random 4 before your media query in the CSS
but I can’t help you, I see all tests passing

Yes, I took at the 4 and added "and on screen to the media query. Maybe I will restart the browser. Thanks again.