Is this a bug in the solutions?

This is what seems to be the most efficient and correct response to this step given the previous steps taught. However, it’s found to be wrong and I cannot see, for the life of me, a reason for the miscoloring that’s going on. This is the first time we’re using the property “display” and a value called “block”, however, given their characteristics, this shouldn’t be how how they behave as there should be no conflict.

img {
  display: block
  margin-left: auto;
  margin-right: auto;

This gives the intended effect and is considered wrong since we’re supposed to be practicing “nesting” code. However, if you notice, the properties and values are being used in the same way.

I may just be missing something, if anyone could help out, please?

Thanks in advance.

Edit: Missing semicolon. I really need coffee.