I can’t see anything wrong with your code. When I cut and paste into the challenge, it passes for me. Try copying the text, resetting the lesson and then pasting again (or just typing it again)?
The thing I don’t understand is that there’s obviously some reason why ‘aspect-ratio’ isn’t being recognised as a CSS property in the code which you posted… resetting sometimes fixes random stuff.
Your solution works from my end. Please try one of the following steps to move forward.
Click on the “Restart Step” button and force a refresh of your page with CTRL + F5 then try to paste the code in again.
or - Try the step in incognito or private mode.
or - Disable any/all extensions that interface with the freeCodeCamp website (such as Dark Mode, Ad Blockers, or Spellcheckers), and set your browser zoom level to 100%. Both of these factors can cause tests to fail erroneously.
or - Ensure your browser is up-to-date or try a different browser.