Why my UI color like a shxxxt

See? The audio track is too different than the homepage showed. When I selected some part, I cannot regonize which part. Not like the CoolEdit at the same OS same machine.
I am using the Windows 11 22H2, and Audacity 3.2.1

Try the high-contrast theme: it’s more obvious there what’s been selected,
(but it’s still not the same strategy as cool edit, which is more suited to your extreme waveforms.)

You also seem to have a LOT of [u]clipping[/u] (distortion). :stuck_out_tongue: … Or at least potential clipping. Audacity itself can go over 0dB (100% or 1.0) but most formats, and your analog-to-digital converter, and digital-to-analog converter are hard-limited to 0dBFS.

It is possible to have a waveform that looks like that without obvious clipping distortion …
loud (-9dB RMS) k-pop.gif

(It is difficult to see the selected audio in that case, until you zoom-in).

I tried each theme, but the selection is similar, I cannot see it clearly

How about multi-view of waveform and spectrogram …
waves and spectrogram.gif