Rob,
Sorry I missed getting back to this message sooner. Didn't mean to forget about you.
No problem about being a beginner. We're here to help... it's our job to simplify things!
Yes, you should be able to put that code anywhere in the template.css file. Ordering does matter in the CSS file, but you wouldn't have any other references to those tags (.jlinkedShare, etc), so those will be the 'first' commands for those tags wherever you put them. Hope that makes sense...
If they were showing on two lines, that's likely an indicator that the column you're trying to put all 4 into is simply too narrow to handle all 4... so, the browser is wrapping the contents to two lines. That can be fixed in a few ways. To not make you do too much investigation, or basically, break your brain
, can you post a URL of where the share buttons are and we can hopefully provide some specific CSS for your site to fix it.
Thanks,
Alex