Repetition:

The action of repeating something that has already been said or written.

Contrast:

The state of being strikingly different from something else, typically something in juxtaposition or close association.

CSS:

Cascading Style Sheets is a style sheet language used for describing the presentation of a document written in a markup language.

Content:

The things that are held or included in something

Margin:

The edge or border of something.

"Musicians play their instruments, I play the orchestra."