My comfyui dark mode often fails, causing some UI styles to be black with black text on a black background.

### What problem are you experiencing?

When I used the portable version of comfyui, I encountered that the dark mode was not adapted, resulting in many UI styles with black backgrounds and black fonts, which was dazzling. I finally solved this problem by adding "color-scheme: dark" in :root or html style. I don't know if it's just me or if most people have encountered it, so I wanted to give feedback and see if I can help.

### When does this problem occur?

Every time you open a web page after startup

### How often do you encounter this problem?

Multiple times per day

### How much does this problem affect your workflow?

Minor annoyance

### Current workarounds

user.css Add to :root{ color-scheme:dark; }，or add to html of style middle

### Ideas for solutions (Optional)

_No response_

### Additional context

_No response_

Start by reproducing the dark-mode page after portable ComfyUI startup and inspect the frontend's root or HTML styles; the issue names no specific file or test. Compare the affected styles with the user.css workaround using color-scheme: dark, then verify that dark-mode pages no longer show black text on black backgrounds.

Written by the indexing model from the issue text.