Can colors of two top most bars be adjusted?

[Thy Grand Voidinesss]

Can this brown color of the bar holding name of window be changed? [In CorelDRAW it is possible]

And how to change color of background of the bar hosting the main menu?

[void]

Can this brown color of the bar holding name of window be changed?

No.
The window frame is managed by the system.

To turn the window caption off:

• In Everything 1.5, from the Tools menu, click Options.
• Click the Advanced tab on the left.
• To the right of Show settings containing, search for:
  caption
• Select window_caption.
• Set the value to: false
• Click OK.

I will consider adding support for a customizable window frame.

Thank you for the suggestions.

And how to change color of background of the bar hosting the main menu?

To set the menu bar background color:

• In Everything 1.5, from the Tools menu, click Options.
• Click the Fonts and colors tab on the left.
• Set Item to: Menu
• Click the color button to the right of Background color.
• Select a new color and click OK.
• Click OK.