Let’s hold off on styling for a moment. You have a few typos in your HTML some of which will affect your ability to style.
In the HTML section click on the down arrow in the upper right corner and then click on ‘Analyze HTML’. Use that to fix/correct your code.
Btw, you have a typo in the CSS section when you try and style the main id.
If you compare the main block with the image block you’ll see something after #main and before the curly brace that you don’t have for #image. And as you know, #image is working and #main is not.