[Feature Request] Mermaid Align Support

[ProudBenzene]

Hello! Everything about the Anu theme makes me feel perfectly adapted. Currently, I heavily use the Anu theme and find it very comfortable.

However, recently I encountered a problem. My mermaid flowchart can only be aligned to the left by default in the theme, and there is no option to adjust its alignment. I hope that the theme can add positioning and layout options for mermaid charts. Thank you!