All art is a combination of objective and subjective aspects.
The objective improvements from css here include: shorter lines are easier to read (per multiple legibility studies), the styling distinguishes navigation and secondary site elements from the main content (without css you get a half screen of navigation links), and the visual importance of in-page anchor links is reduced.
The objective improvements from css here include: shorter lines are easier to read (per multiple legibility studies), the styling distinguishes navigation and secondary site elements from the main content (without css you get a half screen of navigation links), and the visual importance of in-page anchor links is reduced.