Spaces don't work in the title of assets. Replace all spaces in the image name with %20 in your CSS, or change the file name to feature underscores or hyphens in the place of each space.
Fix #1
background-image: url("The%20More%20You%20Know1.gif");
Fix #2
Change the file name to TheMoreYouKnow.gif and update your CSS accordingly.
If the file still doesn't load, check your file structure to make sure that your GIF is located in the same directory as your index.html file. If it isn't, you need to navigate to it in your css like this:
background-image: url("/images/The%20More%20You%20Know1.gif");