Consider doing the same for your images. You're currently using a URL but since you've included the actual images in your repo anyway, you should just use their relative paths so the images are always visible on your site.
Thank you for all your comments! I'm endeavoring to use a relative file path for the Secret Agent project, but I can't get the syntax correct for doing so (there's so much conflicting info online!)
https://github.com/jennykijowski/Tea-Cozy/blob/master/index.html#L6
Good job using a relative file path to include your stylesheet.
https://github.com/jennykijowski/Tea-Cozy/blob/master/index.html#L36
Consider doing the same for your images. You're currently using a URL but since you've included the actual images in your repo anyway, you should just use their relative paths so the images are always visible on your site.