details element The HTML details element (<details>) is used as a disclosure widget from which the user the retrieve additional information, h3 element Heading Level 3, strong element Specifies that the enclosed text should be rendered in the browser as "strong" (usually bold) text. These elements allows child elements from interactive, embedded, heading, sectioning, phrasing, and metadata content categories.
Click the html element name in the punctuation list to advance the example in 'Tryit-Editor':