Through the magic of WordPress.com shortcode.
I have spent around 12 hours yesterday and more than 4 already today trying to find a way for the CSS colors on my theme stylesheet page to show [hopefully with line numbers]. Copy and paste does not work–not in the blog, Microsoft Word, nor WordPad. I tried online code formatting, I tried screen captures and Optical Character Recognition, and on & on… Formating/highlighting is stripped from text to be pasted for some reason. BUMMER!!!
None of those worked. I spent LOTS of time researching “How-Tos.” The last place I looked gave me a solution that works, albeit without the colors I see in my Twenty Sixteen CSS Page, but colors none-the-less, even with line numbers.
Line numbers make it easier to reference the code for questions, on to go back to the place one wants to return to. For me, I can easily change single items. The first line number is set to 15 to match my CSS line numbers.
I could have put up an image file that has all the colors; but, you would not be able to copy the code.
I trust my enhanced Twenty Sixteen Custom CSS Page helps and will make its use easier.
I will do the same soon on my Twenty Fifteen Custom CSS.