Bigger, Better input
I am stuck in
You are missing a couple of semicolons and a closing curly brace there.
I would also recommend that you avoid using uppercase on your selector (index) and your property names (font-size). It isn't forbidden and may not be an issue, but just to be consistant.
That's looking much better!
That lonely semicolon at the bottom is not required, it may even be causing a syntax error. Delete it.
Now, you just need to add a closing curly brace to complete your new CSS rule.