The demo shown below was taken from the official Mermaid documentation.

requirementDiagram

  requirement test_req {
  id: 1
  text: the test text.
  risk: high
  verifymethod: test
  }

  element test_entity {
  type: simulation
  }

  test_entity - satisfies -> test_req

Textual representation

requirementDiagram

  requirement test_req {
  id: 1
  text: the test text.
  risk: high
  verifymethod: test
  }

  element test_entity {
  type: simulation
  }

  test_entity - satisfies -> test_req

The code above is rendered by "Prism Syntax Highlighter for Confluence" which supports highlighting Mermaid syntax.

👉 Check out the official Mermaid documentation here https://mermaid.js.org/syntax/requirementDiagram.html.