The colors of page content , sidebar and page header are the same.

[allyson-silva]

The page header and the side menu always have the same color, making it impossible to differentiate between them regardless of the theme used. I suggest that the top bar have a slightly darker tone than the theme's default for better differentiation. Additionally, the content should also have a different tone to create a visual hierarchy and improve readability. For example, the content could have a lighter tone than the top bar, or it could use a different color altogether.
Example:

[saadeghi]

They don't have colors by default.
You can add any color to them like bg-base-200 or bg-base-300 or even Tailwind color names if you want.

Let me know if you have a question.