Mermaid graph CSS class

Example with a CSS class in a Mermaid graph (flowchart)

HTML

<html>
  <head>
    <script src="https://cdn.jsdelivr.net/npm/mermaid/dist/mermaid.min.js"></script>
    <script>mermaid.initialize({startOnLoad:true});</script> 
  </head>
  <body>
    Diagram 1:
    <div class="mermaid">
      graph TD
      A --> C
      B --> C
      class C myClass;
    </div>

    Diagram 2:
    <div class="mermaid">
      graph TD
      C --> D
      C --> E
      class C myClass;
    </div>
  </body>
</html>

CSS

.myClass > rect {
    fill: #ff0000 !important;
}