Example

%%{init:{"theme":"base", "sequence": {"mirrorActors":false},"themeVariables": {"actorBkg":"red"}}}%%
sequenceDiagram
    Bert->>+Ernie: Start looking for the cookie!
    Ernie-->>-Bert: Found it!
    Note left of Ernie: Cookies are good
    

%%{init:{"theme":"base", "themeVariables": {}}}%%
sequenceDiagram
    Bert->>+Ernie: Start looking for the cookie!
    Ernie-->>-Bert: Found it!
    Note left of Ernie: Cookies are good