How to make translucent window works in dark mode effect, while the mac system is in light mode

How can I make translucent window in dark mode effect, while the mac system is in light mode?

All my css works perfect in system dark mode.

When system is in light mode, and obsidian color scheme is dark mode, side bars and top bars go white.

I find no way to use css to turn obsidian transparent, unless turn on translucent window in obsidian setting.

Does obsidian get the system translucent window effect? So the side bar and top bar become white. Is there anyway to keep obsidian in dark mode, while my MacOS is in light mode?

Or is there anyway to let single app in dark mode, while MacOS is in light mode?

Any suggestions are precious. Thank you!

Newbie to CSS here.