Another major advantages of CSS are that it allows being picked up by search engines better, because of clearer code

CSS allows getting picked up by search engines:
When you use CSS to structure your pages, it is possible for you to hide content from specific browsers in certain situations. For example, you may want certain content to appear only in print or you would like some content such as page navigation only to get displayed on the screen and not in print.

Using CSS gives you the advantage of getting content indexed along with the benefit that content brings. Assuming you are new to CSS, you must understand that many browsers still interpret CSS standards in their own ways. Some of the archaic browsers do not read CSS at all.

While structuring your pages using CSS, you must ensure that that they have the maximum cross browser compatibility and that HTML pages appear acceptable even without CSS.