TreeMap title unreadable on dark backgrounds

[DavidSeptimus]

Description

TreeMap title is unreadable on dark backgrounds irrespective of theme.

Steps to reproduce

1. Create a treemap with a title
2. Set your background to a dark color
3. Use the dark theme
4. The treemap title is black and can't be changed without a custom stylesheet

Screenshots

Light - Visible title text

Dark - No visible title text

Code Sample

https://develop.git.mermaid.live/edit#pako:eNpdj0tPwzAQhP-KtQe4hMp2nEdzQy0PCZBAICEhX9x4SSIcO3IdCaj630kCpQT7tPPtzGh3UDqNUEDwiK3qzjYYlLShCQbJozK4JWsVFHkQhFMupB0-nBtD7r3TfRm2EqQlw5NwYbAM3tmm_BW_wX3tLA5aQVhC6V9yq7rguglxOkdPamMwTCg_EAkr40Ld2GpecIf2dNr8F__s2gPJkhm5afQkx8fo62GZnJAr5TXaef5l720Teo-jRcw71lg6_3MARFD5RkMRfI8RtOhbNY6wGx0SQo3tlCFBK_82luwHT6fsi3PtweZdX9VQvCqzHaa-0yrgulGVV8cVtBr9yvU2QJHyKQKKHbxDwViyEDEXLMmzPBWcLSP4GORcLEQuaBLTLFnmSRrvI_icWukiEzHjaZ4wShnnKdt_AZkSljk

Setup

• Mermaid version: v11.12.1+39d070f
• Browser and Version: Chrome 142.0.7444.176

Suggested Solutions

No response

Additional Context

No response