I’m fairly new to coding, but my understanding is that by using CSS you can apply multiple styles to an element or any number of elements by defining the attributes in a CSS class and so not have to have a long list of class definitions in the html.
I find that this makes my code easier to read (by read i actually mean fix when it doesn’t do what I expect) and also keeps styling seperate and easier to find should i chnage my mind later about what i want it to look like. For ecample, if i’ve defined and applied a class in more than one place, then i only have to amend it once in the CSS and not in several places in the HTML.
For short challenges where you don’t need to apply a style more than once it probably won’t matter so much in terms of the end result, but as challenges become more complex seperating your styling will be a god send so it’s a good habit to get into I believe.
I hope that helps