@Codemiester, when a test fails click the red button to see which test(s) are failing and text to help you correct the issue.
Be sure and read more than just the first line of the failing message. The ability to read and comprehend error messages is a skill you’ll need to acquire as a developer. Ask questions on what you don’t understand.
The failing message says;
On regular sized devices (laptops, desktops), the element with id="navbar" should be shown on the left half of the screen. It should always be visible to the user and should remain stationary. You may need to enlarge the viewport or zoom out to ensure the navbar doesn't scroll with the page content.
Left of bounding rectangle is not correct.: expected 86.328125 to be at most -445.34375
AssertionError: Left of bounding rectangle is not correct.: expected 86.328125 to be at most -445.34375
When looking at your page, no matter what the screen size the nav is always at the top.
According to the user story it should be on the left and stationary for regular sized devices.
It’s okay to have it at the top on small screens.
The W3C validator is giving you a warning and letting you know about semantics which are new in HTML5.
You can choose to ignore the warning or implement the fix as @bbsmooth explained.