Why override user-defined styles?

[GreedyPirate]

Proposal

Here is my demo link: https://jsfiddle.net/jaynnay/mgkedpth/
As you can see, I have defined a class .myClass, and I need to add !important to override the Mermaid default styles, as shown in the image below.

But if I need to define a complete set of flowchart styles, this approach would be very inconvenient. Is there a better solution for customizing styles?

Example

No response

Screenshots

No response