How do I extend the margin in the title box of my project?

So here is the project I’m working on : FCC Survey Page
I want to make the top box extend throughout the width instead of the small margin it has.
I haven’t added the margin in the code and I’m not understanding how to make it work

different browsers have different default styling for html elements, here your body tag has a margin of 8px, set it to 0 and you are good to go!

yes I was looking at the inspector and found 8px margin and was wondering how did that happen

thats why its prescribed to normalize or reset the default styling!