Add styles for font sizes

- [Instructor] Adding theme support for editor-font-sizes…does exactly that,…adds new font sizes into the editor.…That means I can set up a new post,…just like I've done here,…with a series of different paragraphs…where I assign different font sizes.…So this first one, I just typed it out and did nothing.…It automatically receives the Normal font size…because the Normal font size…corresponds to the standard font size in the theme.…Then I set up another one that has the Small font size,…one that has the Large,…and one that has the Extra Large size.…Now all of this looks correct in the editor right now…because we provided editor with all the information…it needs to make this happen.…

However, if we jump to the front end,…you'll see all of these paragraphs have the same font size,…and that's because we have yet to provide the CSS…to tell the theme how to size these different fonts.…Looking at the markup for each of these paragraphs,…you see what's happening here is the same thing…that happened with the colors.…When we apply a new font size,…