Just about any element can have styling information associated with it. For example, This is a span with a blue color style. There are lots of different styles - we can look up what all the options are when we need them. If you use a good IDE, like Visual Studio Code, it can tell you for some of them.

Styles "cascade" - that is if we style one element, the elements inside of it also get that style. Unless they override it. For example, this is one span with another span inside of it.

In this, the paragraph has a style (it's green). So if I put a span inside of it I can override it.