What does a semicolon outside of curly braces do?

Question

This has had me tearing my hair out for an hour:

div {
  key: value;
  ...
};

img {
  key: value;
  ...
}

(Note the semicolon after the curly brace). None of the styling for imgs was showing up ... finally I noticed the semicolon and removed it -- voila! it all works as expected.

The question: what does a ; outside of curly braces mean?

Answer 1

what does a ; outside of curly braces mean?

Invalid syntax.

That's why the parser stopped there and didn't pick up any of the style rules below (e.g. img). Validate it yourself.