An online document is a tree composed of multiple block elements. Different types of BlockElement can nest different element types. For example, a highlight block can nest any BlockElement, while a paragraph block can only nest InlineElement. The overall structure of a document is as follows:
BlockElement can nest different element types. For example, a highlight block can nest any BlockElement, while a paragraph block can only nest InlineElement. The overall structure of a document is as follows:
Take this document as an example. The page can be broken down as follows: